My brother's bestfriend

Tessa has always had a thing for Joel, ever since the day her twin brother Miles brought him home for dinner for the first time when they were eight. Joel always saw Tess as just his best friends sister until the summer before high school. Miles has made it clear that if Joel ever tries any of his fuck boy ways on Tessa he will end up dead, but senior year feels like the time where rules need to be broken.