It's a romcom genre i think? The mc is a bishi, rich highschooler but he Suck when it's about love mc always fail whenever he try to approach a girl. Actually there is a girl that like him but he reject her cuz he already like other girl but turns out it fail. Then he pathetically chase the girl that was like him before but she already date another man even worst he tried to get in between them. In the end he still single until the end of series

Maybe Naze Toudouin Seiya 16-sai wa Kanojo ga Dekinai no ka?

Ah, yes that one thank you