Toraneko no Shitsukekataトラネコのしつけ方

The cute-faced but super strong at fights delinquent - Kotarou, and the excellent, sports all-rounder honors student - Yamato. The two are seen as polar opposites, but they​'re actually in a lovey-dovey relationship. Seeing his beloved Yamato's nape and lips fills Kotarou's mind with "perverted thoughts". But when he's touched, he panicks and throws a punch...?!