Main Characters
- Famous Ancestor: Most students in the series are "descendants", people who are distantly related to various folklore figures across the world and have abilities related to them.
Kazushige Sanda
Voiced by: Ayumu Murase (Japanese), Edward Mendoza (English)
The Hero of this story, who is the thirty first descendant of Santa Claus. He can switch into his other form by wearing any sort of red clothing item and reverts back to normal by consuming a type of candy called Bratty Beans.
- All-Loving Hero: Sanda is a good-natured and trusting-to-a-fault kid through and through, and this is only strengthened when his Santa powers activate: As the symbol of childhood dreams and wishes, he’s determined to protect every child from harm and refuses to kill anyone who comes after him.
- Death-Activated Superpower: His Santa powers are awakened after Shiori stabs him in the heart. (Though it’s left unclear if it’s the death that triggered it or him getting red on him) Afterwards, he’s shown to have an extreme Healing Factor in his Santa form.
- Idiot Hero: He’s… very much not the brightest bulb. In fact, his Establishing Character Moment shows him using some Insane Troll Logic to believe that Shiori is planning on giving him a Love Confession despite the fact that she’s just chased him around the classroom with a knife and outright proclaimed that she was going to kill him after school. One of his roommates lampshades how utterly absurd it is for him to draw this kind of conclusion.
- Living Lie Detector: One of the passive powers he gets after his Santa transformation, even in his child form, occurs is that objects are toppled over or destroyed whenever somebody in his vicinity tells a lie.
- Meaningful Name: His last name sounds a lot like "Santa". Many a joke is had at his expense.
- Nom de Mom: "Sanda" comes from his mother's side. His father married into her family rather than the other way around.
- Older Alter Ego: Sanda is a 14-year old boy whereas his Santa form is a man in his '60s.
- Power-Up Food: Inverted. In order to turn back into his 14-year old self, he needs to eat a gummy candy called Bratty Beans. This presents a problem for him when they stop being produced...
- Transformation Trinket: Kind of; he transforms into Santa Claus whenever he gets anything red on him. He usually uses his school’s sports jacket for it, but blood is also demonstrated to work.
- Strong Family Resemblance: He definitely takes more after his mother than his father. The fair hair and youthful face come from her.
Santa Claus
Voiced by: Hiroki Tochi (Japanese), Ben Balmaceda (English)
Father Christmas himself and the alter ego of Kazushige.
- Cool Old Guy: Being Santa Claus himself makes automatically like this. That being said, he's a muscular old man who can hold his own in combat.
- Friend to All Children: Invoked. As Santa Claus, he has to be a positive figure for children or else he'll lose power. Being able to transform into Santa also hinges on him not falling in love or having dirty thoughts about children, even if Sanda is only a kid himself.
- Healing Factor: Santa is basically immortal and can heal from any injury no matter how severe it is. The one exception to this is reindeer blood.
- Immune to Fire: He'd have to be in order to slide down people's chimneys.
- Older Alter Ego: Is this to Kazushige
Shiori Fuyumura
Voiced by: Umeka Shoji (Japanese), Morgan Berry (English)
A tall, lanky, and withdrawn middle school girl who is willing to commit dangerous acts out of a desire to find Ono with the help of Sanda's dual identity.- Ax-Crazy: Her Establishing Character Moment involves her drawing a knife on Sanda in order to make him bleed and trigger his Santa transformation, and even afterwards, she’s quick to bring on the violence on anybody who stands in her way. Her growing friendship with Sanda does mellow her out as the story progresses, however.
- Huge Schoolgirl: At 183 cm, Shiori is exceptionally tall for the average Japanese person, let alone Japanese woman. She towers over most of the people around her as a result.
- Lady Looks Like a Dude: Her scrawny build and Boyish Short Hair, coupled with the school’s unisex uniform, makes it easy to mistake her for a boy.
- Mad Bomber: Her Weapon Of Choice is explosives. Her first test of Sanda’s newfound Santa powers involves her planting a bomb in the classroom and tasking him with finding them before they blow everyone to kingdom come. It turns out that she was wearing them on her person the whole time.
- Not So Stoic: Her Perpetual Frowner expression does give way for genuine despair and sorrow on occasion, such as when Ono and her undress in front of each other once Ono was returned with a more mature body, making Shiori realize just how big the gap is between them now, and Ono’s death causes her to have a complete teary meltdown after Sanda manages to wear down her mental defenses.
- Perpetual Frowner: Her default facial expression is a dour scowl with Exhausted Eyebags, and she’s basically never shown smiling from the heart.
- Really Fond of Sleeping: Despite sleep being forbidden at the school for the sake of keeping the children from developing adult bodies, Shiori does it anyway and seems to have it as a bit of a hobby. This serves to be useful to Santa, as he gets a power boost from children’s dreams.
- Tomboy and Girly Girl: The Tomboy to Ono’s Girly Girl.
- Used to Be a Sweet Kid: Despite her facial expression being as flat when she was a child as it is when she’s a teenager, Shiori was shown to have been an affectionate and sweet girl before her father became so obsessed with building up his cult that he forgot that the whole reason he went as far as he did in the first place was in order to make her happy. The trauma of her upbringing messed her up pretty badly.
Hitoshi Amaya
Voiced by: Yūki Shin (Japanese), Jonathan Leon (English)
A classmate to Sanda and Shiori. After a brief stint as an apparent antagonist, he turns out to also want Santa and Christmas to become celebrated again in so his parents' cake shop can be saved by selling Christmas cakes. After the situation gets cleared up, he becomes one of Sanda's closest allies.
- Meaningful Name: His last name contains the kanji for "sweet", and he's shown to be quite the skilled sweets maker. Furthermore, his parents are shown to run a cake shop.
- Supreme Chef: He's an exceptionally skilled baker and candy maker, which comes in handy once the Bratty Gummies stop being made and he needs to create a substitute to let Sanda become a kid again.
Others
Ichie Ono
Voiced by: Anna Nagase (Japanese), Abby Trott (English)
Shiori's closest friend who went missing. A part of her still believes in Christmas.- The Lost Lenore: It's shown that her relationship with Shiori went beyond just a close friendship, but that they were actually in love. Her death causes Shiori to become even more cold and distant than previously before her dam finally bursts.
- Shes All Grown Up: Played for Drama. It turns out that the reason she went missing was because she fell asleep after a night of implied intimacy with Shiori, causing puberty to hit her like a truck. Knowing that the school would go after her if they saw her no longer having a childlike body, she decided to flee. Furthermore, her entering puberty so fast took a big toll on her body... such a big one, in fact, that she's revealed to be dying when she returns.
- Still Believes in Santa: Despite living in a world where childhood myths were left forgotten decades ago, Ono still believes in them. This is why Shiori seeks out Santa Claus, as she believes that Santa can use this belief to find Ono after she goes missing.
- Your Days Are Numbered: Her entering puberty all at once did some severe damage to her body, meaning that once she enters the story again, she's shown to be close to dying. She passes away at the end of the School Festival after spending her final moments with Shiori.
Niko Kazao
Voiced by: Misato Matsuoka (Japanese), Brittany Lauda (English)
Hifumi Oshibu
Voiced by: Toshihiko Seki (Japanese), Lucien Dodge (English)
The Headmaster of Daikoku Welfare Academy. He's determined to make sure his students follow his rules at any cost.
- Cyborg: He admits that he can't stop the march of time from claiming his body, but lord knows he'll try. Most of his body, at this point, is steel and cybernetics holding up whatever flesh is left. Near the end of the series, he's not even eating food anymore, preferring to get his nutrition from oil and molten steel.
- Huge Guy, Tiny Girl: Because age hit Toyo harder than it did Oshibu, she comes up to, at most, his knee, while he towers over her and several adults. They were much closer in height in their youth.
- Kill the Ones You Love: Ochibu strangles Toyo to death after one last bout. The act is consensual, not that Sanda is able to comprehend that by walking in on them in the moment.
- Older Than They Look: He's really 92 years old, but he uses plastic surgery to retain his youth. Only his hands look his proper age.
Saburo Yagiuda
Voiced by: Hiroaki Hirata (Japanese), Kirk Thornton (English)
Toyo Tetsudome
Voiced by Masako Nozawa (Japanese)
- Miniature Senior Citizens: She's not only tiny, she's shorter than most of the children as well!
