کاینکو

A monster that forms a 'bond' with Amamiya when they meet.

He is able to communicate with him by a hair-like antenna on Tetsu's head.

On command he can morph into almost everything, like a big bowl of pudding or stapler; [Spoiler: in the end Cenco even shapes himself as a human arm to replace Tetsu's right arm he sacrificed in the fight.]