It takes the dumbest-sounding logline in the season, a chubby middle schooler who hulks out into Santa Claus, and makes you sit up straight by episode three. Paru Itagaki's brain is all over this: the same Beastars instinct for bodies as arguments, so the transformation isn't a gag but a horror, a kid's frame stretched into something adult and enormous while the state hunts him with an actual Saint Nick Pursuit Unit. The worldbuilding is the flex. A Japan so starved of children it warehouses them in Daikoku Welfare Academy as protected assets, with every rule following that skewed logic straight down. Fuyumura cornering Sanda over a missing classmate is the engine, and she is written with teeth, not as a prize. Notably, a school anime with zero interest in leering at anyone. The animation wobbles and the last stretch idles, but nothing else this year looks or thinks like it.
In a future Japan where children have become precious and rare, Christmas exists only in history books. Santa Claus is no longer folklore but a genuine threat, hunted by government operatives whenever sightings occur. At Daikoku Welfare Academy, a heavily monitored boarding school, students live under constant surveillance for their own protection. Shiori Fuyumura's best friend vanishes without warning and is declared dead six months later. Refusing to accept this conclusion, Shiori begins investigating in secret. Her search leads her to an impossible theory: the boy who sits next to her in class, Kazushige Sanda, might be connected to Santa Claus itself. Whether as descendant, accomplice, or something stranger altogether, Shiori becomes convinced that Sanda holds the key to understanding what really happened to her friend. What begins as a personal search spirals into something far larger. The line between myth and reality blurs as Shiori uncovers dangerous secrets the academy has worked hard to bury. Trust becomes a luxury neither of them can afford.