The uncle would be related by marriage, not blood, and would probably be somewhere around 25-40ish. I'd like the niece to be 18-22ish.
I want them to build an emotionally intimate relationship before fucking like animals.
She's a college student, an eclectic mixture of bookish, down to earth, and a slightly rogueish tinge to her personality. Powerful and sharp minded, she exudes an electrifying sexual energy, though she's quite selective in who she'll fuck. Lynette Jane Anderson is playful, flirty, confident, and happy with her life and where she's at. She even remains optimistic when she gets laid off and tries to find another job to pay for her rent. When her search yields no results and she gets evicted, she moves in with her uncle--who's in the midst of a separation/divorce with Lyn's father's sister.
As for the uncle, he's maybe known her since she was a little kid, perhaps a toddler. He could've gotten along with her while her aunt offered to take care of Lynette, and her brother, while their parents were on vacation during summer break, a few years prior to this. Or maybe they've only socialized awkwardly at family events. Either way, I'm thinking Lyn has a certain distaste for her aunt, and fortifies her uncle's decision to get a divorce--subtly, of course. As she spends more and more time with him, she ends up developing a romantic interest in her uncle. They have some deep conversations, he tells her about his life and she tells him about hers. He's a bit of a square, and she ends up being a sort of corrupter, smoking cannabis and drinking with him after their friendship develops a little bit.
Of course, this is all up for discussion!
Possible pictures for Lynette (tell me if you like one of them) - Eins Zwei Drei