Two best friends, Simon and Lin, are in their final years of highschool. But not Mei. Mei is the annoying, younger sister of Simon who somehow butts heads with her brother at any given encounter. She has just started her first year at the same highschool, briefly crossing paths with Simon and Lin. And honestly? That's all she needed to get her brother's best friend to fall head over heels for her. Even with Simon's explicit warning for Lin to 'not hit on his little sister'.