ガチャンキイ

Jikkai High, with a low academic score of just nine, is a bottom-tier school where delinquents from all over the country gather, with new transfer students arriving almost every week. Our protagonist, Jou Sago, is terrible at fighting and spends his days being looked down on by everyone... but everything changes when the strongest of them all, Goku Hitomi, transfers in. (Source: MANGA Plus)