: The guest yōkai whose "passionate" tennis coaching becomes the center of a media firestorm.

: Hihi's demanding regime leads to public outcry after the press gets involved, accusing him of various forms of harassment.

: After Hihi is exposed as a yōkai by Nezumi-otoko, Yumi eventually finds a much more literal form of "unbreakable defense" by hiring the wall-yōkai Nurikabe as her new coach. Key Characters