Kachuna is the story of Jun Mizushima, a high school student who suffers from what is known in Japan as the 'eighth grade syndrome', or the 'chuunibyou syndrome'. Jun is someone who genuinely believes that he has superpowers. Aside from that, he's also really determined to create a game of his own and compete in the annual International Game Development Competition for the Youth. With him are his friends: Takahiro, an awesome programmer; Tsumiki, a dazzling writer; Yui, an energetic musician; Ai, a talented artist; Megumi, the enthusiastic club advisor; and Shiro, Jun’s annoying little sister and avid supporter.