Male. Reddish hair and blue eyes. Exceptionally handsome. He only likes Yasuke and only smiles for him. He is dissatisfied with everything (except Yasuke). He is the reincarnation of the great yokai Senya (Byakuran). Because Senya was Yasuke's foster son, Yasuke is reminded of Senya every time he looks at Senkichi, leading Senkichi to attempt running away from home repeatedly, though he fails every time. He believes he is Yasuke's biological brother (in reality, they are not related).

Male. Black hair and black eyes. Senkichi's older brother. A yokai babysitter. He is around twenty years old, though even he doesn't know his exact age. He feels sad whenever he sees Senkichi because it reminds him of Senya. He tries his best not to think of Senya in front of Senkichi. He seems close to Kyuzo, yet they fight frequently.

Female. A hanyo (Father: Kyuzo, human; Mother: Hatsune, yokai). Kinne's twin. Black hair and black eyes. She never wants to be apart from Kinne. She is a bit short-tempered. (Refer to Kinne). Daughter of Kyuzo and Hatsune.

Female. A hanyo (Refer to Amane). Black hair and black eyes. Amane's twin. She looks so much like Amane that only Hatsune, Kyuzo, and Senkichi can tell them apart properly. She is surprisingly persistent. Her ability is distinguishing between humans and yokai. Daughter of Kyuzo and Hatsune.

Male. Black hair and black eyes. He cherishes Hatsune, Amane, and Kinne so much he would risk his life for them. The landlord of the tenement house where Yasuke lives. He is quite wealthy and was raised as a precious child. He used to be addicted to alcohol and gambling, but he changed 180 degrees after getting married.

Female. Black hair and black eyes. A princess of the Kasha tribe who married a human. She can teleport. A typical mother figure (gets angry when necessary and gives praise when deserved).

Female. A rabbit yokai. She takes the form of a large rabbit during the day but becomes human at night. She always carries a rabbit mask on her back. She frequently uses the interjection 'Umm—'.

Male. The head of the Royal Fox tribe. He is the magistrate of the Eastern Underground Palace. He is Tsuyumi's uncle and dotes on her, showing kindness only to her. Described as an incredibly beautiful young man. He enjoys wearing flashy clothes (e.g., red silk). A great yokai with immense spiritual power. He wears a half-broken ogre mask.

Female. A cat yokai and the Queen of Cats. Described as a beautiful girl with long white hair and golden eyes. She has a fickle personality and enjoys collecting human soul beads.