Shoujo Manga Shujinkou x Rival-san

A girl named Kimura-san is trying to get closer to her crush, Mizushima-kun. However, another girl, Hiyama-san, who is both attractive and argumentative, opposes this. The nature of her objection, however, is unusual and does not follow typical expectations of such situations. The story is presented in a serialized format in Gangan Joker and contains one additional chapter beyond the main series.