Ranpo Kitan: Game of Laplace

The story begins at a middle school where the murder and dismemberment of a teacher has taken place. Kobayashi, a boy who goes to this school and the lead suspect in the case, meets the genius detective Akechi, who comes to the school to investigate. After being cleared of the crime, Kobayashi takes an interest in Akechi and, in spite of his friend Hashiba's worries, volunteers to be Akechi's assistant. (Source: Wikipedia)