|Debut Episode||Awakening Arc, Episode 2|
Chuuni-senpai is the pet cat living in Rin and Len's house. He is sometimes seen with a frog plushie and often wanders around. Unlike the other animals, Chuuni-senpai does not have a set person that he normally hangs around.
- One of the official Wooser account managers were revealed to have a cat of Chuuni-senpai's breed in real life.
- He also happens to be an indirect reference to Rikka Takahashi of the "Love, Chuunibyou and Other Delusions" franchise alongside his own name, which may have been taken after the term "Chuunibyou".