Hitchhiking teen seduces housewife

18 year old young woman manages to bum a ride and a place to crash for the night from a nice middle-aged woman she meets in a grocery store parking lot. Housewife is a bit nervous about letting a stranger into her house but decides it's her Christian duty, besides, her daughter and husband will be home so she won't be alone...until she receives calls from both of them that they will be away.

Still, the girl seems nice and dinner goes well. Only she seems to be very touchy feely, complimenting the older woman's figure and touching the parts she finds so attractive. The woman can't help but fantasize a bit as well when the girl asks her to help with figuring the shower out and gets to see her young guest completly nude.

So that night, it's little surprise when the woman hears her door open and hears clothes hitting the floor right before a pair of lips Meet hers.

But what happens the morning after? Do they go their separate ways? Does the woman find a way to keep the girl nearby? Does the girl rob her blind? Does more of the family get seduced? Is the hitchhiker a werewolf?

In the morning, the hitchhiker is nowhere to be found. The housewife starts hanging around the grocery store parking lot, hoping to run into her again. She starts driving around near highway off-ramps, looking everywhere. She even gives rides to other hitchhikers, hoping to relive the experience, even if it has to be with someone else. She finally dies of a broken heart, unaware that the original hitchhiker was actually a galactic space traveler, and has returned to her home planet.

Minus the dying part I really like that take

The woman offers her the vacant garage apartment, and totally gets her groove back.

The husband comes home early and finds his wife and the hitchhiker girl, and after an awkward introduction, they have the girl pinned between them. He's not worried about his kids finding out since both his son and daughter are living in a dorm at college.

Hubby wakes up around 4AM to find the girl is missing from his bed, and worried that she's stealing them blind, he goes looking without bothering to get dressed. He hears sounds from the media room and sneaks around the door. In the light of the TV, he sees three naked people.

The hitchhiker girl is on her back on the floor, his son is between her legs, and his niece is riding her face. Niece tries to cover herself, but starts her orgasm as she locks her eyes onto her uncle's manhood. He gives her a wink and backs away, and only niece knew he was there.

The man goes back to bed, working through in his mind how he'll deal with her when he's not exhausted. Wife feels his iron rod poking her and makes him even more tired.

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ETA: Incest is a category I won't do, but uncle/niece is as close as I'll get. Plenty of opportunity for all kinds of directions for the story to go now.