Seiko Ayase is a character from the manga series Dandadan, a supernatural-themed story that blends elements of horror, action, and comedy. Seiko is depicted as a fiercely protective and caring grandmother to one of the main protagonists, Momo Ayase. Despite her age, she possesses extraordinary spiritual abilities, allowing her to combat supernatural threats. Her role is crucial in guiding and supporting the younger characters in their battles against various paranormal entities, making her a formidable yet loving figure in the series.