Seiko Ayase

Seiko Ayase (綾瀬 星子, Ayase Seiko) is a spirit medium and Momo's grandmother, though her youthful appearance suggests she is in her 20s. Despite lacking innate supernatural abilities, she possesses vast knowledge of curses and yōkai, using enchanted artifacts and the power of a local deity—effective only within the city—to exorcise spirits. Brash and aloof, she often frustrates others, particularly due to her susceptibility to flattery and her refusal to admit that aliens exist, but remains deeply protective of Momo and her allies. She also hosts a television program where she demonstrates genuine spiritual feats such as fortune-telling, which has made her surprisingly wealthy.