Sibling story where sister never shows off cleavage until she joins brother in pool or hot tub after a date

[Trioxydone]

I've been looking for this story for weeks and I haven't been able to find it through literotica itself or google or anything, so I turn to this forum as my last resort. I cannot remember the names of the characters, I just vaguely remember the brother coming to live back home, he's got an injury in his leg I believe and it slowly builds up the relationship between him and his sister. She never wears anything that reveals her cleavage, which she explains is because she only wants to show that to someone she's actually properly interested in, so after a while she gets asked out by a guy from her work and they both want to acknowledge what has been growing between them, but the brother is still uncertain whether or not he should say something to stop her from going and then he notices she's going with a shirt that completely covers her chest still. He then sits in a hot tub drinking beer to block out his woes until she comes home from the date and joins him in the pool with a very revealing bikini and they profess their love etc.

I truly have no other idea how to find this story anymore, even though I can still remember most of the entire plot, which has been quite frustrating. So I hope someone else recognises this who can point me to the story!

Thanks in advance!