Shoujo Manga Shujinkou x Rival-san

Synopsis

Kimura-san wants to get close to her crush Mizushima-kun, but the beautiful and confrontational Hiyama-san has a problem with that... though it's not the kind of problem you'd expect from this scenario. Note: this is the pre-serialization version posted on the author's twitter and later released in volumes by Gangan Joker.