1Everything's Bright, Am I Aging?
On a Dec 25 without Christmas, Sanda is attacked by classmate Shiori. Mistaking it for love, he awaits her confession, but hears something else.
2Candies, Canes, Kisses, and Blades
Amaya learns Sanda is Santa, restrains him and Shiori to force a kiss. Santa refuses, unlocks sled power to escape. Then Headmaster Oshibu appears!
3Charred Fruit Tastes All the Sweeter
Sanda gains lie-detecting power. Shiori tries to use it to find Ono, but doubt overwhelms Sanda. Shiori then tells a self-harming lie.
4Zeus, Smasher of Textbooks
At a funeral, Santa fights Yagiuda but fears his power. His resolve returns, shattering the roof and leaving him exposed before all.
5A Typhoon in a Snow Globe
Sanda vows never to love, but in a typhoon his message to fiancee Niko fails and he's drawn to her. The next day, Yagiuda arrives as a teacher.
6Cyborg vs. Santa Claus
Santa blocks Headmaster Oshibu from attacking adult Ono, but the enhanced 92-year-old overpowers him. Santa asks the kids for their belief to fight.
7Double-Faced Carnivorous Plant
Amaya ends his friendship with Sanda to save him. Meanwhile, the scarred Oshibu, comforted by Yagiuda, turns to Class 10 students who killed adults.
8Love, the Most Selfish Thing There Is
Saved from Namatame by Shiori, Santa vows to harden his heart, but when Niko asks for a kiss, Sanda panics and almost transforms before her.
9A Fake Flower, Yet Its Roots Rot
Tetsudome says Santa lacks grit. With her aid Sanda becomes dark Santa, but doubts himself. After meeting Namatame again, he vows not to fight kids.
10You, an Everlasting Moment
At the Peak of Youth Ceremony, Niko steals Sanda's first kiss at twilight. Meanwhile Yagiuda faces Namatame alone, offering himself as decoy.
11Flashback Attack
Namatame wrecks the ceremony. Eating yakisoba, she's met by Sanda in child form. His body starts breaking down as Ono's own changes grow.
12Pale Blue Pall
Santa fights Oshibu before the students. The headmaster thrives on cheers, but Santa regains power by revealing his truth. The duel peaks on the roof.