Incest, ageplay, dub-con
—Going too far... (Older sister or slightly younger)
It's been a while since your brother had gotten a sick interest on you, what at first (at least as far as you knew that is) started with just innocent brushes, an out of character interest on being near you and "accidental" events fully developed into full on harassment. Maybe you let it pass out of innocence, a worry to get you or him on trouble or just a mild interest on what he was doing but now this has gone too far and you don't find the strength to speak up or still have hope that it'll end soon, that he'll get bored or (and just maybe, deep down, you want him to go further and see how far he'd go.
(Ive other plot ideas if interested but I'm mostly wanting to play this one with a character similar to her of possible)