Tomodachi x Monster

In a small mountainous village in rural Japan, strange creatures lurk. It's here that young Wataru hears a voice calling out to him. Wandering from his school, he soon discovers a new “friend” that will transform his life forever – or drastically shorten it. Wataru learns of a hidden world of monsters who seek to befriend young children, and together with them enter a horrifying death match.

(Source: Seven Seas Entertainment)