Seiko Ayase (Santa Dodoria)

The ability to see spirits

Seiko has the ability to see spirits, such as territorial spirits and youkai.

Divination

Seiko demonstrated an ability to gather information about people, such as easily uncovering Shoma's secrets.

Borrowing power

Seiko can borrow power from deities residing in various regions. The primary location where she borrows power is the city of Kamigoe, where she resides.

Mystical barriers

By borrowing powers from the deities, Seiko is able to erect barriers that can banish evil spirits and those under curses. She does this with the help of her nail amulets and talismans.

The barrier's primary power lies in its ability to repel evil spirits, using flame to reduce them to ashes. The barrier's lethality increases if more than one nail is driven into the ground.

Because her barriers are only effective if the deity from which she borrows power is nearby, Seiko is limited to exorcising evil spirits within the area where that deity resides. In exchange for the privilege of wielding the deity's power, Seiko is also required to visit temples for three days as a sign of gratitude. Although this condition was established after Seiko borrowed power from the Hokkaido deity, it is unclear whether the conditions differ for each deity from which she borrows power, whether the condition is imposed by Seiko or the deity, or whether temple visits are a standard condition associated with borrowing power.

A highly respected medium, Seiko is known for her profound knowledge and understanding of spirits. Her ability to exorcise evil spirits from people and places is considered exceptionally high among the most experienced mediums, as five of them, previously hired by the Enjoji family to rid their home of the Eye of Evil, recommended Jiji Seiko as a last resort after their own failed attempts. Seiko possesses exceptional hand-to-hand combat skills, demonstrating advanced martial arts skills in her confrontation with the Jiangshi and defeating them single-handedly. Her skills were also highly praised by Enenra, despite Seiko's defeat. Seiko primarily fights using Nessie's bat to overwhelm her opponents. She can wield it with one or both hands. A two-handed grip allows her to deliver more powerful blows, powerful enough to knock down opponents and leave dents in their wake. Along with this weapon, she uses talismans and amulet nails to exorcise spirits within the barriers she creates. If she doesn't have a weapon at hand, Seiko can use improvised materials, such as a piece of wood, which serves as a bat. Seiko is a skilled cook and occasionally demonstrates her skill in preparing various dishes for the Family.

Seiko possesses strong strategic skills: she devised a plan to lure Turbo Granny outside of Shono City into a trap to exorcise her and the Crab Spirit, and also orchestrated the operation to rid Rin of Ombusman. During the battle with Turbo Granny, who had taken over Okarun's body, Seiko anticipated its attack from a blind spot and erected a barrier there in advance. She also prepared another barrier trap for the youkai, allowing her to strike Turbo Granny with a bat from various angles, knocking her back into the barrier and further igniting it.

Seiko demonstrated physical prowess beyond that of a normal human. In her battle with the Eye of Malice, she demonstrated the ability to channel enough force into her bat to knock the yokai down with a single swing, leaving a crater in the ground. She also demonstrated impressive speed and reflexes, being able to avoid the Eye of Malice's attacks in close combat.

Despite being a grandmother, Seiko looks like a slender woman in her prime. She has long white hair, which she wears in a high ponytail. She also wears red-framed glasses. She is a heavy smoker, so she is often seen smoking. In addition to her youthful appearance, Seiko is noted for her beauty, which is often mistaken for Momo's mother. She is taller than her granddaughter.

In public, Seiko wears a yellow open cardigan with buttons, underneath which she wears a crossover top, a blue baseball jacket with white sleeves and a symbol on the back, large hoop earrings, and sandals. At home, she wears a white tank top, shorts, a beige haramaki belt, and light gray arm warmers with matching mid-thigh leggings.

As Dodoria Santa, Seiko wears a mask, gloves with pointed fingers, and a cloak that covers her entire body, leaving only her hair visible.

In the past, when Momo was a little girl, Seiko wore a shrine maiden robe and tied her hair in a simple ponytail.

Seiko has a phlegmatic personality but a rather blunt manner of speech. At the same time, she sympathizes with those in need and helps them, for example, by providing shelter in her home. Instead of accepting compensation from Okarun for looking after him when he was cursed by Turbo Granny, she responds that the only way to repay her is by helping others in need. When interacting with children, Seiko believes that, as an adult, she should shoulder their burdens so they can freely pursue their dreams. Therefore, she was upset that she was unable to fulfill Jiji's wish to help him control the Eye of Evil and save the youkai from exile. Despite her willingness to help others, Seiko is too proud to admit that she needs help herself or to burden others with her problems. So, she initially refused the help of Okarun and Mister Mantis Shrimp to rebuild her home, which was destroyed by the Eye of Evil.

Seiko can sometimes act frivolously, such as when she joked about Momo's crush on Okaruna due to their namesake status, and also when she forced her granddaughter to impersonate Abe Hiroshi in exchange for a new school uniform. Despite this and her unfeminine manner of speech, Seiko can act politely if she feels she's made a mistake that affects the well-being of others. This side of Seiko is considered rare and uncharacteristic by those who know her well. Although she claims to never give in to emotions, Seiko subconsciously favors those who compliment her, such as her youthful appearance, of which she is very proud.

As a medium, Seiko follows the rules of coexistence between the living and the dead, which include not showing disrespect to the dead and sending them to the afterlife, using force if necessary if they decide to attack the living.