Yuigadokusonmaru

Yuigadokusonmaru (唯我独尊丸, Yuigadokusonmaru), often called just Dokusonmaru (独尊丸, Dokusonmaru) for short, is Kasuka Heiwajima's cat. He is mentioned in passing a few times in the light novels and appears in the anime.

Adabashi Arc
He is sent to live with Anri Sonohara to protect him from Kisuke Adabashi. He runs away after Kisuke attacks Anri and he is saved by Mikado Ryuugamine.