Gusha to Yokukai no Leviathan
愚者と欲界のレヴィアタン
A middle schooler named Tetsu Makaino desires nothing more than to make friends and live an ordinary life. His sincere longing draws the attention of the demon Leviathan, who proposes a deal: Tetsu's body in exchange for supernatural abilities. This agreement leads to an occurrence referred to as "A Feast of Demons."