Momoo Inugami

A masochistic dog god that is usually summoned by Momiji. He is capable of transforming into a chihuahua, and becomes Ichiko's alliy after experiencing a swift punishment (since he is masochistic) from Ichiko when his cover is blown in episode 5.

He would sometimes drop by Ichiko's place hoping to experience the same punishment again.

(Source: Wikipedia, ANN)