My Bestfriend's Sister

Kara Danvers is on her last year of high school and her sister and friends come down to visit for a week. Lena's presence makes Kara question herself in a way that's never happened to her. Lena Luthor doesn't date, but when she sees how grown up her best friend sister has become, will things change? Will Kara Danvers be the one to change everything for the cynical Luthor? Or will both of them get hurt in the process?

Supercorp AU