Ataru Natsumeda is a reserved first-year high school student struggling to differentiate himself. Unfortunately, his solitary and melancholic life is exacerbated by his parents' tense relationship, and his sister Tsukimi's superlative intellect and beauty. One day, a group of bullies begins to torment Ataru in their attempts to intimidate Tsukimi. During this event, Nirasaki, Ataru's classmate, observes Ataru's reaction and suggests that he should have rebelled against the bullies. In a surprising, turning point, Nirasaki gives Ataru a "wishing stone" through a kiss, saying that it can fulfill any desire.
Now the owner of the wishing stone's incredible power, Ataru uses it to conjure up a brutal fate for those bullies, and they die inexplicably. As Ataru confronts the reality of his actions, he questions the source of the stone and Nirasaki's identity. As he delves into the grim world of the wishing stone, everything takes a turn for the worse, leaving Ataru feeling uncertain about what lies ahead.
