My Dear Loser (2017)

Oh, known to everyone as Mushroom, has been bullied all his life. Even by Copper, who used to be his best friend and is now the most popular guy in high school and the head of a group of bullies. But this year Oh is going to challenge himself when he falls in love with Copper's beautiful girlfriend, Peach. But he won't be alone. Sichone a girl who needs to find classmates to form a club for the HQ will reclute Sun, a transfer student who also gets bullied, In one of the bullies who gets expelled from the group, and Oh. And together they will discover who they really are.