How to deal with a sexy best friend

[8letters]

SimonDoom recently created a thread, "What you expected when you started writing here". One of my expectations was that the AH would be a place where writers posted the challenges they were facing in their current story to get advice from fellow writers on how to best to handle that challenge. I thought then I'd learn a lot about writing just from reading such discussions. But I rarely see such discussions, which makes me a little sad. So here's me posting what I thought the AH would be all about when I first discovered the AH.

I'm writing a brother-sister story called "A Flirting Workshop with My Sister". The narrator is Eli (college sophomore), and his sister is Z (college freshman). Z's best friend is Katharine. Our first description of Katharine:

Z said, "You remember Katharine Newton?"

I smiled. "Of course. She came over all the time." Katharine was a cheerleader who liked working with Z on school projects. She was one of the prettiest girls in my high school with long, brown hair and a gorgeous smile.

"She was a big flirter, right?"

"Right." She flirted with me every time she came over. Just a little, but enough to get me revved up. She’d make me feel like the most special person in the world.

Z was a nerd in high school. During her senior year, Katharine suddenly became close friends with her.

"I had bitched to [Katharine] plenty of times that guys were never interested in me because I was so smart in math and sciences. One day, I was telling her that again and she said, ‘Let's change that’. She did a complete makeover of me. She got me on a cheerleader diet and a cheerleader work out program. She helped me buy a new wardrobe. She got me a new hairstyle," Z swung her hair slightly, "She taught me how to brighten my hair color and what product to use to improve its fullness and shine. She taught me about make up. She guided me through smile practice."

So Katharine is a gorgeous, hot, master flirter that Eli had a crush on his senior year of high school. The middle part of the story is Katharine putting on a flirting workshop with Eli being the guy flirted with. Katharine is very in-charge, says several funny lines, and regularly demonstrates she knows how to press guy's buttons.

The problem with the initial version of the story was that Katharine was just far more appealing than Z. When Eli fell in love with Z, it didn't make sense because he was so much more attracted to Katharine. I like Katharine the way she is, but how do I sell that Z is a better choice for Eli to fall in love with?

 

[SimonDoom]

This seems right up your alley! I'm sure you can handle this challenge.

Katherine is more obviously hot and more self assured than Z, but that doesn't mean the reader necessarily has to like her more or want Eli to end up with her. A few things you can do:

1. Katherine has to have a flaw. Something in her personality. Maybe she's not exactly a Mean Girl, but she's a bit stuck up, or perhaps overly aware of her attractiveness -- something that turns off the reader, just a little bit, and makes Z seem more sympathetic.

2. Give Z and Eli something in common -- a trait, an intellectual interest. Z apparently is highly intelligent. Maybe Eli too is highly intelligent, and Katherine doesn't share that. She's not smart enough for Eli. It takes Eli a little while to realize that and to appreciate his nerdy sister.

3. The "Save the Cat" concept I referred to you in an earlier thread -- have Z do something for Eli that make the reader especially sympathetic to her. Make it relatively early in the story, so you plant that seed that Z is an appealing person. Perhaps she does something nice for Eli that Katherine didn't think to do.

4. Katherine isn't interested in Eli. She's so convincing with the flirting workshop that he mistakenly thinks she's actually interested in him, and is crushed when it turns out she isn't, and then Z steps in and he realizes Z is more appealing.

5. Tell the story from Z's point of view. Then you have a kind of Cyrano de Bergerac situation. Z is falling for her brother, and over the course of the workshops realizes that what is really happening is that she's falling for him and is using Katherine to capture his interest, but she realizes it's starting to backfire when he's becoming interested in Katherine. I think this would be a cool challenge because you usually tell the story from the male POV -- you could write a story exactly in the same manner that you usually do but from a different POV. If you tell it from her POV then you don't have to delve into the mind of the brother -- she's the sympathy figure that the reader pulls for and you've got your problem solved.

 

[JGittes]

Have Eli and Z both be participants in the workshop. Z is working with her friend Katharine on the workshop and at first Eli's attention is naturally directed to Katharine but Z learns flirting from Katharine as well and over the course of the workshop, learns to out flirt the teacher and get Eli's interest. The end of the workshop is a kiss set up by Katharine, thinking it will gross them out, between Eli and Z where everyone's real romantic interests become clear.

 

[SimonDoom]

Another more subversive and challenging approach would be to make Z a LESS nice person than Katherine, but in a way that makes her more interesting. This is the Gone With The Wind idea -- Scarlett loves Ashley Wilkes, who is a much more honorable person than Rhett Butler. But readers want Scarlett to end up with Rhett, because she's a rascal just like he is, although she can't admit it, and they're meant for each other, although it takes 1000 pages for her to figure that out.

 

[NotWise]

Eli and Z have a long background together, shared experiences, and similar thinking. Their common traits overwhelms physical appearance. Love is blind, you know.

 

[HordHolm]

Some good advice here. If I might add a small piece of my own... Is Katherine already in a relationship? If she is the danger is that Eli wants her more - can't have = want. If she's single and not interested it's much easier, though she's great, so there will need to be a reason that she's single. The thought occurs that she could be gay (and perhaps only now realising it), thus adding a whole new angle to the Katherine, Eli, and Z dynamic...

 

[8letters]

This seems right up your alley! I'm sure you can handle this challenge.

Katherine is more obviously hot and more self assured than Z, but that doesn't mean the reader necessarily has to like her more or want Eli to end up with her. A few things you can do:

1. Katherine has to have a flaw. Something in her personality. Maybe she's not exactly a Mean Girl, but she's a bit stuck up, or perhaps overly aware of her attractiveness -- something that turns off the reader, just a little bit, and makes Z seem more sympathetic.

2. Give Z and Eli something in common -- a trait, an intellectual interest. Z apparently is highly intelligent. Maybe Eli too is highly intelligent, and Katherine doesn't share that. She's not smart enough for Eli. It takes Eli a little while to realize that and to appreciate his nerdy sister.

This is what I more or less settled on doing. I decided to see if people had more suggestions.

3. The "Save the Cat" concept I referred to you in an earlier thread -- have Z do something for Eli that make the reader especially sympathetic to her. Make it relatively early in the story, so you plant that seed that Z is an appealing person. Perhaps she does something nice for Eli that Katherine didn't think to do.

This is an interesting idea. Nothing comes to mind on how to do it, but I'll let my mind percolate on it.

4. Katherine isn't interested in Eli. She's so convincing with the flirting workshop that he mistakenly thinks she's actually interested in him, and is crushed when it turns out she isn't, and then Z steps in and he realizes Z is more appealing.

I have this somewhat in my story. I think leaning too much on this would backfire - Z shouldn't be a consolation prize after Eli loses out on Katharine.

5. Tell the story from Z's point of view. Then you have a kind of Cyrano de Bergerac situation. Z is falling for her brother, and over the course of the workshops realizes that what is really happening is that she's falling for him and is using Katherine to capture his interest, but she realizes it's starting to backfire when he's becoming interested in Katherine. I think this would be a cool challenge because you usually tell the story from the male POV -- you could write a story exactly in the same manner that you usually do but from a different POV. If you tell it from her POV then you don't have to delve into the mind of the brother -- she's the sympathy figure that the reader pulls for and you've got your problem solved.

This would entail throwing out all 33K words I've written, not something I'm interested in doing.

If I was willing to do that, I wouldn't do it as I think the story is better from the MMC POV. The flirting workshop is a third of the story and is to me a male fantasy. I don't think a FMC would enjoy watching the person she has feelings for flirting with other women.

 

[LAHomedog]

Love and attraction is one of the great mysteries of life. I have talked about and written that I never understand why woman are insulted when a guy gets a boner looking or thinking of them -- not doing anything offense, just getting hard.It's a tremendous compliment. Arousal is nature's biggest compliment to another. We cannot control arousal it just happens and there are many triggers.

We talk a lot on here about kinks. Mine involves short redheads with pert tits, tight asses who are spinners and like anal. So after a parade of those young women through my bed I married a tall, very large breasted women with breeder hips. Why? I fell in love with her. Not her body -- even though the large breasts and red hair help -- I fell in love with her. The person, the woman, the mind.

I realized that I am a sapiosexual. A person who is sexual attracted to intelligence in others. That's it. I fell in love with her brain. (I wrote a story about being a sapiosexual titled "Jane Bets Her Ass.)

Anyway why can't Eli realize that he is a sapiosexual and even though his little head might be screaming for Katherine, his mind tells him he wants Z, and he is actually aroused, attracted, and desires only Z. It is her brain that gets him hot.

You can write a very compelling, hot story around being attracted to the person not their body. The great writer Fran Lebowitz wrote, "You can't rent pretty." I've fucked dozens of cute, pretty girls, but after a night so what. At some point you have to have a conversation. It's her brain not her body. Make it about the connection between the two of them.

 

[Ginlover]

For Katherine to have so much knowledge on flirting she has done it a lot. In your quoted text she knew how to make herself physically appealing — hair to how to smile

Imply she is a slut. Eli can think she is hot but not want to fuck someone so easy and just become a notch on her bed post. Readers on here instantly dislike women who have had multiple previous partners, they prefer a sex goddess to be natural and have not needed practice, it sounds like Katherine has had lots of practice lol

 

[8letters]

Have Eli and Z both be participants in the workshop. Z is working with her friend Katharine on the workshop and at first Eli's attention is naturally directed to Katharine but Z learns flirting from Katharine as well and over the course of the workshop, learns to out flirt the teacher and get Eli's interest.

I didn't say this earlier as I was trying to keep things brief - the workshop is one night for a few hours. Not nearly enough time for Z to overcome Katharine's years of experience.

The end of the workshop is a kiss set up by Katharine, thinking it will gross them out, between Eli and Z where everyone's real romantic interests become clear.

Interesting suggestion, but doesn't work for me. It'd take extraordinary circumstances for a brother and sister to seriously kiss in front of other people, and I don't think a kiss in such circumstances would move the relationship that far forward.

 

[lovecraft68]

My opinion is that if you're goal is for a brother/sister to fall in love, then no other girl can compare to her, that's why the taboo is worth breaking, you should not love your sister, but she's so special, and beautiful etc that he can't help it

So having sis have this perfect superior in every way friend isn't going to make the sibling love plausible.

Also the readers will be annoyed because...wtf with Katharine, he's supposed to want his sister.

I guess you could run with the sister having the attraction to the brother first, then being jealous of her friend, that might work, but in general giving sis a rival may not be easy to deal with.

 

[8letters]

Another more subversive and challenging approach would be to make Z a LESS nice person than Katherine, but in a way that makes her more interesting. This is the Gone With The Wind idea -- Scarlett loves Ashley Wilkes, who is a much more honorable person than Rhett Butler. But readers want Scarlett to end up with Rhett, because she's a rascal just like he is, although she can't admit it, and they're meant for each other, although it takes 1000 pages for her to figure that out.

That would be really hard to do. It'd requiring making both Z and Eli interesting but flawed characters. It's tough doing that with one character. Very interesting idea, but I don't think that fits this story. I think it would have to be a very long story to make that work (though hopefully not the size of GWTW).

Some good advice here. If I might add a small piece of my own... Is Katherine already in a relationship? If she is the danger is that Eli wants her more - can't have = want. If she's single and not interested it's much easier, though she's great, so there will need to be a reason that she's single.

Through most of the story, all we know about Katharine's love life is that Z says at one point that Katharine is "driving the guys at her college crazy." She's the type that goes through a lot of boyfriends. So she might be dating someone, but that wouldn't stop her from moving on to a new relationship.

The thought occurs that she could be gay (and perhaps only now realising it), thus adding a whole new angle to the Katherine, Eli, and Z dynamic...

I'm thinking they are going to be lots of comments requesting a sequel with a threesome between Eli, Z and Katharine.

For Katherine to have so much knowledge on flirting she has done it a lot. In your quoted text she knew how to make herself physically appealing — hair to how to smile

Imply she is a slut. Eli can think she is hot but not want to fuck someone so easy and just become a notch on her bed post. Readers on here instantly dislike women who have had multiple previous partners, they prefer a sex goddess to be natural and have not needed practice, it sounds like Katherine has had lots of practice lol

Katharine is very experienced sexually. I think that makes her more appealing. Eli thinks about her at one point, "If anything were to happen between us, it’d be a shallow bit of frolicking. Still, it’d probably be damn awesome shallow frolicking."

 

[NotWise]

My opinion is that if you're goal is for a brother/sister to fall in love, then no other girl can compare to her, that's why the taboo is worth breaking, you should not love your sister, but she's so special, and beautiful etc that he can't help it

So having sis have this perfect superior in every way friend isn't going to make the sibling love plausible.

Also the readers will be annoyed because...wtf with Katharine, he's supposed to want his sister.

I guess you could run with the sister having the attraction to the brother first, then being jealous of her friend, that might work, but in general giving sis a rival may not be easy to deal with.

I think this can be worked around. My two most-favorited I/T stories are sibcest stories with another girl involved. In "My Sister's Wedding" they had kind of a long-standing three-way instigated by the sister. In "Watch Me" the brother fell for the sister's best friend and the taboo relationship followed.

 

[Bramblethorn]

2. Give Z and Eli something in common -- a trait, an intellectual interest. Z apparently is highly intelligent. Maybe Eli too is highly intelligent, and Katherine doesn't share that. She's not smart enough for Eli. It takes Eli a little while to realize that and to appreciate his nerdy sister.

For instance:

Katherine half-closed her eyes, and tilted her face towards mine. My lips brushed hers, and then -

"They're kissing again!" Z said. "Do we HAVE to hear the kissing parts?"

"What are you—" began Katherine, but I already knew the expected reply. "Some day", I said in my best Peter Falk voice, "you may not mind so much!"

Katherine disengaged. "What on earth are you talking about?"

"It's from a movie," I said. "Z and I watched it over and over when we were kids."

"Inconceivable!" exclaimed Z, and we both started giggling.

- Reinforces E and Z's shared history
- Shifts the dynamic from "intimacy between E and K, with Z being the third wheel" to "E and Z bonding while K is left on the outer". (Just recently we were discussing how pop-culture shout-outs can alienate readers who don't recognise them; here, you can use that within the fiction to alienate Katherine.)
- Sets up for a second Princess Bride echo later in the story - since the framing device of that film is about a kid who starts out opposed to romance but eventually gets caught up in it, there are several snippets that could work well in a story about siblings starting to feel attracted to one another.

For instance, this adapts nicely:

"I wasn't nervous. Maybe I was a little bit concerned, but that's not the same thing."
"Because we can stop now if you want."
"No. You can read a little bit more, if you want."

And then, hey presto, you have an recurring theme of the siblings' shared background being what brings them together. I'm not much of an I/T reader but I think that kind of thing plays well there?

 

[lovecraft68]

I think this can be worked around. My two most-favorited I/T stories are sibcest stories with another girl involved. In "My Sister's Wedding" they had kind of a long-standing three-way instigated by the sister. In "Watch Me" the brother fell for the sister's best friend and the taboo relationship followed.

This is where it comes down to factions. The true 'incest romance' readers will still be put off by your premises. The "ohh, incest and with another party" will like it.

I did a mother/son story where the mom and the son's girlfriend seduce him into a threesome(more to it, but we don't need details here) and it did not go over as well as straight up mom son.

Now...starting with another partner and the MC not being happy with them, but their family member can love them better so to speak can rank up there...

Again, it falls under some will like it, some won't. The purists won't care for it, the fans of simple taboo will go for it.

 

[SimonDoom]

This is where it comes down to factions. The true 'incest romance' readers will still be put off by your premises. The "ohh, incest and with another party" will like it.

I did a mother/son story where the mom and the son's girlfriend seduce him into a threesome(more to it, but we don't need details here) and it did not go over as well as straight up mom son.

Now...starting with another partner and the MC not being happy with them, but their family member can love them better so to speak can rank up there...

Again, it falls under some will like it, some won't. The purists won't care for it, the fans of simple taboo will go for it.

Hold on, now -- aren't you talking about something different?

I'm completely with you on the threesome problem. Incest fans like their incest pure. It's kind of the whole point of an incest story. The connection is so strong that it transcends the taboo AND non-incest connections.

But it's a whole different matter if Eli starts off by being attracted to Katherine and realizes over the course of the story that his REAL interest is his sister Z. Handled correctly, that story should fly just fine with incest purists, because the end result is Eli is all-in with the incestuous relationship with the sister. The key, though, is the author has to sell the reader on the fact that the sister, who's not as hot as Katherine or as flrty, is the better match. I think there are many ways to do that, but that was 8Letters' original question and I think he's right that this is the thing that the story needs to nail down.

 

[NotWise]

Hold on, now -- aren't you talking about something different?

I'm completely with you on the threesome problem. Incest fans like their incest pure. It's kind of the whole point of an incest story. The connection is so strong that it transcends the taboo AND non-incest connections.

But it's a whole different matter if Eli starts off by being attracted to Katherine and realizes over the course of the story that his REAL interest is his sister Z. Handled correctly, that story should fly just fine with incest purists, because the end result is Eli is all-in with the incestuous relationship with the sister. The key, though, is the author has to sell the reader on the fact that the sister, who's not as hot as Katherine or as flrty, is the better match. I think there are many ways to do that, but that was 8Letters' original question and I think he's right that this is the thing that the story needs to nail down.

I don't think I agree with either of you. Maybe I'm just not sure what an incest purist is. Maybe if I appealed just to the purists, I'd have higher scores.

But wait! Part 3 of "A Valentine's Day Mess" includes a long story about a guy who loves his sister, but marries her best friend, and has babies by both of them. That story held a score around 4.9 for five months. It isn't that high now, but it's still my highest-scoring story in I/T -- except for a couple of late chapters with an insignificant number of votes.

 

[MillieDynamite]

This kind of dynamic in the story would make a very natural, pistol hot, conflict to build the story to whatever the conclusion would be.

 

[BuckyDuckman]

The problem with the initial version of the story was that Katharine was just far more appealing than Z. When Eli fell in love with Z, it didn't make sense because he was so much more attracted to Katharine. I like Katharine the way she is, but how do I sell that Z is a better choice for Eli to fall in love with?

First off, I would ignore any advice about tailoring the story to fit the incest purists. Writing to please the masses seldom does and often comes across as forced.

Thought #1: Perhaps you're making the mistake of thinking you're writing an incest/taboo story when you're not?

Thought #2: As attracted to Katharine as Eli feels, he could be intimidated by her experience or concerned that she could never be exclusive enough for him. A porn star might seem like a great fuck, but do you really want to marry one? (No offense to any porn stars. If I wasn't already married, I'd date and marry you!)

Thought #3: Perhaps not the point of your story, but it could be interesting for Eli to move past the thrilling flash of Katharine being a good flirter and find more joy in his sister's less effective flirting techniques.

• Her earnestness could be compelling.
• He might fall in love with the taboo element, so while she's not as good at it as Katharine, it means more to him on a deeper level.
• The strength of her effort attracts him in a way that Katharine's effortless skill could never match.
• After her cheerleader diet, makeover, and exercise program, who's to say that Z doesn't being to outshine Katharine? And, if that's the case, it's simply a matter of describing those improvements.

 

[SimonDoom]

I don't think I agree with either of you. Maybe I'm just not sure what an incest purist is. Maybe if I appealed just to the purists, I'd have higher scores.

But wait! Part 3 of "A Valentine's Day Mess" includes a long story about a guy who loves his sister, but marries her best friend, and has babies by both of them. That story held a score around 4.9 for five months. It isn't that high now, but it's still my highest-scoring story in I/T -- except for a couple of late chapters with an insignificant number of votes.

You're right. There are plenty of examples of stories that break almost any rule you can think of. "Rules" aren't really rules. They're just observations about what's most common. Nobody has to do with what's most common.

Much of this is just my personal taste. I like an erotic story to maintain a tight focus on a particular fetish or kink. I feel its erotic power is diluted if it drifts over too many different topics. But there are readers who like that greater variety, too.

 

[8letters]

My opinion is that if you're goal is for a brother/sister to fall in love, then no other girl can compare to her, that's why the taboo is worth breaking, you should not love your sister, but she's so special, and beautiful etc that he can't help it

So having sis have this perfect superior in every way friend isn't going to make the sibling love plausible.

Also the readers will be annoyed because...wtf with Katharine, he's supposed to want his sister.

I guess you could run with the sister having the attraction to the brother first, then being jealous of her friend, that might work, but in general giving sis a rival may not be easy to deal with.

Original story idea:
>>>>>>>>>>>>>>>
I'd think it'd work better if the brother says something like "I wish you'd stop flirting with my friends when they come over. You're terrible at flirting." The sister gets offended and starts flirting with the brother to show that she's a good flirter. And the real reason the brother wanted his sister to stop flirting with his friends was that he has a thing for her that he's been fighting to suppress and her flirting with his friends was making him jealous. And the sister was flirting with his friends because she knew she was making him jealous and liked it.
<<<<<<<<<<<<<

That idea didn't go anywhere. Another idea I've had floating around for a long while is that the friend of the sister gets off on being evil and talks the sister into having sex with her brother. I used to have a porn clip where the brother is asleep in a chair by the pool, the innocent sister and the slutty friend come out, the slutty friend convinces the sister to wake her brother by sucking his dick, and that leads to a long, hot threesome. That was my favorite porn scene, and I lost it at some point switching computers.

So then I had the idea of the flirting workshop. Pure male fantasy. But I had a story that worked for me. Z would be the innocent sister. Katharine would be the evil best friend who wants to corrupt Z into having sex with her brother. The first part of the story would be Z flirting with Eli's friends in front of him (Katharine is secretly encouraging her to do that), the second part would be the flirting workshop lead by Katharine, and then third part would be Z and Eli becoming a couple.

So I wrote my first draft and sent it off to someone to get their thoughts. And their feedback was that Katharine was far hotter and more appealing than Z, and that it made no sense for Eli to fall in love with Z instead of pursuing Katharine. Oops! That wasn't what I intended. But I like Katharine as she is, and I think her being the way she is makes the story work better. So I am doing a major rewrite to keep Katharine as this attractive sex goddess, but to make Z someone Eli would prefer over Katharine as a romantic partner.

Right now, here is what I have for Eli's thoughts towards the end of the flirting workshop:
>>>>>>>>>
And then there was Katharine. My, oh my, Katharine. This evening reminded me why I had always been in lust with her. But she had said a couple of things that made it clear that she wasn’t the type of girl I wanted to date. Despite the years of us flirting, I didn’t know much about her beyond that she was an expert at pushing my buttons. Tonight, she had come across so smart, so knowledgeable. Then I remembered Z telling me that if she were to date one of my friends, they’d be disappointed with her as they only saw what she wanted to show them and not the real her. Would Katharine keep her mask up if we were to date this week? Probably, I realized. Suddenly, dating Katharine was much less appealing. If anything were to happen between us, it’d be a shallow bit of frolicking. Still, it’d probably be damn awesome shallow frolicking.

How would this workshop change my relationship with Katharine? I saw her regularly because she was Z’s best friend. I couldn’t picture her acting significantly different than she always had. She’d return to being someone I enjoyed flirting with, to being my favorite sex fantasy, and to being someone I’d never seriously consider as a girlfriend.

What about Z? If she wasn’t my sister, where would she fit in compared with the other girls? I had the more complete relationship with Z than with the other girls. Katharine had been totally right when she said that sex and cheerleading were important to me, but being my best friend was the most important thing to me. Z was already filling the female best friend role. We talked a lot about school and my friends. She had shared earlier today what she had heard from Landon and Rob. She was the one non-pre-med that understood what it was like to be a pre-med. She was my sister and all that, but I was still shaken by how much I had wanted her when she was on the stairs. Had my subconscious know it was Z? Had I been lusting for my sister for a while, and because I could justify not recognizing her my mind went wild with sexual fantasies about her?

Would this workshop change my relationship with Z? I had been impressed by her performance. She had demonstrated a conversational agility that I didn’t know she had. I hadn’t looked to her for an interesting conversation, but I would now. This workshop would give us a special memory, an additional bond, a pleasant secret to re-share. I could see us discussing it frequently in the future when it was just the two of us, comparing things that just happened to what happened during the workshop. This workshop had really opened my eyes to what an attractive woman Z was.

I really liked my sister. I was glad she spent a lot of time with me and my friends. Part of me wished she wasn’t my sister.
<<<<<<<<<<

 

[8letters]

I'm not much of an I/T reader but I think that kind of thing plays well there?

The way I write I/T is that my story is a classic romance with declarations of true love at some point, but between two family members. So anything that would work in a classic romance will work in my stories.

That being said:

For instance:

>>>>>>>>
Katherine half-closed her eyes, and tilted her face towards mine. My lips brushed hers, and then -

"They're kissing again!" Z said. "Do we HAVE to hear the kissing parts?"

"What are you—" began Katherine, but I already knew the expected reply. "Some day", I said in my best Peter Falk voice, "you may not mind so much!"

Katherine disengaged. "What on earth are you talking about?"

"It's from a movie," I said. "Z and I watched it over and over when we were kids."

"Inconceivable!" exclaimed Z, and we both started giggling.
<<<<<<<<
- Reinforces E and Z's shared history
- Shifts the dynamic from "intimacy between E and K, with Z being the third wheel" to "E and Z bonding while K is left on the outer". (Just recently we were discussing how pop-culture shout-outs can alienate readers who don't recognise them; here, you can use that within the fiction to alienate Katherine.)
- Sets up for a second Princess Bride echo later in the story - since the framing device of that film is about a kid who starts out opposed to romance but eventually gets caught up in it, there are several snippets that could work well in a story about siblings starting to feel attracted to one another.

For instance, this adapts nicely:
>>>>>>>>
"I wasn't nervous. Maybe I was a little bit concerned, but that's not the same thing."
"Because we can stop now if you want."
"No. You can read a little bit more, if you want."
<<<<<<<<
And then, hey presto, you have an recurring theme of the siblings' shared background being what brings them together.

"The Princess Bride" is one of my favorite movies. But I haven't watched it recently, so it took me a while to place the dialogue you were quoting, particularly the last one. The scenes with the kid aren't that memorable to me. And my guess would be that if you didn't know "The Princess Bride" really well, all of the dialogue you suggested would fall flat.

 

[MetaBob]

So Katharine is a gorgeous, hot, master flirter that Eli had a crush on his senior year of high school. The middle part of the story is Katharine putting on a flirting workshop with Eli being the guy flirted with. Katharine is very in-charge, says several funny lines, and regularly demonstrates she knows how to press guy's buttons.

The problem with the initial version of the story was that Katharine was just far more appealing than Z. When Eli fell in love with Z, it didn't make sense because he was so much more attracted to Katharine. I like Katharine the way she is, but how do I sell that Z is a better choice for Eli to fall in love with?

I have a similar situation in a piece I'm working on now: a shy young woman named Molly who thinks of herself as too tall and too fat meets a man named Alex who she's interested in. He likes her and they become intimate but she's feeling anxious because his ex, who he stopped seeing in grad school when they both got too busy, now wants back into his life. This is not an incest story, but for the purposes of this thread that's irrelevant.

Molly's office recently hired Cata as a receptionist, and Cata, like Jolene in Dolly Parton's song, could have any man she wants. Confident, experienced, and expert in flirting, sex, and everything in between, Cata knows she could probably take Alex but has no desire to; she's already happy with her life, which currently features "two bulls and a live-in pet". She even comes on to him once and he rebuffs her:

"I'm sorry, Cata. I won't. You are unbelievably attractive, but the life you describe just isn't something I can identify with, even if I'm sure you would excel."

Her smile grew. "I know. Thing is, I don't want that life. I want more. I just needed to know whether you could resist me. Most men I work with become hopelessly enamored, to the point where I won't work with men if I can help it. Barbara told me you might be different, but I had to know for myself. If I'd been able to seduce you I doubt I would've shown up Monday even if the thing I did next was give you the best fuck of your life." She raised her arms over her head and twirled. Her body and her smile were breathtaking. "I'm not done teasing."

Later, Cata and Molly talk:

"First, know your strengths. He's your man, not anyone else's. You need to solidify that strength. Ask for his help, just simple stuff that'll make him feel like you appreciate him, like he has a role to play in making you happy. He wants to protect you, he wants to provide for you; he's a good man and that's his nature. He wants you to know that and whether he'll admit it or not, he wants you to appreciate him for it. You'll need to get stronger and slimmer. You're a stunning woman and even through your loose clothing I can tell you have a wonderful figure, but you have to believe that yourself. When he tells you you're beautiful, and I know he does, he wants you to feel the same way about yourself. And finally, you have to fall in love with yourself if you want him to love you. Trust yourself, trust what effect you have on him, and find ways to make it more profound. I can tell he's good in bed just from the way you touch him and talk with him, but I guarantee he can be much better. You need to take control of that, to guide him. I can ... um ... help."

 

[HordHolm]

Pardon me while I digress for a moment, but I am going somewhere... The discussion around Katherine reminds me of an ancient Roman woman called Clodia Metelli. She was part of the most aristocratic family in 1st century BC Rome, the Claudii, and was known for being the wittiest, best bred, most vivacious woman in Rome, leader of the party set.

But she was also renowned for more negative reasons; it was alleged that she had an incestuous relationship with her brother Publius Clodius (just about the most immoral man in town), though this accusation may have no substance, and may well have been made to smear them both (you think politics now is dirty). And despite her obvious vivacity and sparkling charm, and despite many rumours of affairs, she also earned a reputation, as time went on, of being a prick tease. She would flirt, and drape herself across whoever would further her, and her brother's political aims, but in the bedroom she was as cold as ice.

And perhaps that could be Katherine - loads of guys have dated her, but nothing has ever developed. She has a wonderful exterior, but beneath it there is something stopping her letting go (which sounds sympathetic, actually), or to make her less sympathetic, perhaps she sees dating as a means to an end, a path to improving her social status or getting what she wants. And perhaps Eli learns of this, hence his (perhaps reluctant) understanding that he needs to turn away from her. And at this point, perhaps Z comforts him and things develop.

 

[SimonDoom]

I think this is going to be a hard one for someone to advise you about, because ultimately the whole essence of the story is the relationship/bond/attraction between Eli and Z, and only you can decide what is erotic and interesting to you about that.

I'd offer this one extra tip, though: Whatever it is about Z that ultimately draws Eli to her, don't make it something that comes about entirely through the workshops. The seed should at least be planted right from the beginning that Eli and Z are meant for each other, not Eli and Katherine. Most romances follow this pattern. The reader, right from the start, senses an attraction between Elizabeth and Mr. Darcy, or between Scarlett and Rhett, even if the characters don't sense it or acknowledge it themselves. Z's lack of skills and Katherine's superficial appeal are both obstacles to what is destined to happen from the start. The workshops should help draw out whatever quality is in her to attract Eli, or help open Eli's eyes to her.

The classic pattern in romance stories is that the REAL heroine is more interesting, sensitive, intelligent, and observant than the other rival women. Think Elizabeth Bennett versus her more conventionally appealing sister Jane. We like Elizabeth Bennett and root for her because she is principled and because she's smarter and more observant than anyone else around her -- except Mr. Darcy, her equal.

I would focus on something like that in this story, based on how you've described Z so far, but that's just me.

Or, as an alternative, think of their union as a matter of complementary unmet needs. Each has a need that the other fills, and that ONLY the other can fill.

It could be any number of things. Ask yourself, what would turn YOU on to Z in a story like this? Only you can answer that.