Seiko Ayase

Though she is a grandmother, Seiko looks like a woman at the peak of her prime, slender and so youthful that strangers routinely mistake her for Momo's mother and reel when they learn the truth. Her snow-white hair is usually gathered into a large top knot, she favors red rectangular glasses, and a cigarette is almost permanently at her lips. She takes great pride in a beauty she calls bewitching, and she stands no taller than her granddaughter.

Out in public she layers a yellow open cardigan over a cross-strap top with a blue white-sleeved baseball jacket, hoop earrings, and sandals. At home she switches to a tank top, shorts, a beige haramaki, and grey arm warmers with matching stirrups. Her Santa Dodoria persona hides everything beneath a mask, clawed gloves, and a full cloak that leaves only her top knot showing, while old memories picture her in shrine-maiden robes with a simple ponytail.

Seiko is even-tempered and rough in speech, yet selfless at heart, taking strangers into her home and living by a philosophy of being in it together. Rather than accept Okarun's payment for sheltering him during his curse, she asked only that he pass the kindness on to others in trouble. She believes adults should carry children's burdens so the young can live freely, which left her grieving that she could not honor Jiji's wish to spare the Evil Eye. Proud to a fault, she resists admitting her own need for help and first waved off offers to rebuild her ruined house.

A streak of immaturity runs through her teasing, like joking about Momo's crush on Okarun or making her granddaughter do impressions to earn a new uniform. As a medium she keeps to the rule of coexistence between living and dead, sending hostile spirits on by force when needed. She adores food, holding that living begins with eating, delights in feeding a hearty appetite, and once spent a whole paycheck on a restaurant full of students. She trusts in spirits but scoffs at aliens, dismissing even Mantisian as a kappa, and finds her rare joy in watching television.

Seiko is the trump card her family turns to whenever a threat, spiritual or otherwise, outmatches them. Her physical condition exceeds an ordinary human's, letting her cratering the ground with a single bat swing against the Evil Eye while dodging its strikes at close range. Her tactical mind is sharper still. She schemed to lure Turbo Granny out of Shono City into a trap, organized the operation to free Rin, and once anticipated a blind-spot attack by raising a barrier in advance, then trapped Turbo Granny in a second tight barrier to batter her from every angle.

Her mediumship is celebrated among peers, so much so that five veteran exorcists who failed against the Evil Eye pointed Jiji toward her as a last hope. She is a master of unarmed combat, having downed a pack of kung-fu jiangshi single-handedly, and she fights mainly with her bat Nessie, switching between one- and two-handed grips and pairing it with talismans and charm nails to exorcise spirits through her barriers. Lacking her usual gear, she improvises with whatever is at hand, even a length of wood. She raised Momo from a young age, teaching her a daily ki-releasing ritual that drew bullying and a temporary rift between them before the two reconciled.