History and Culture Research Club

Launched by Dandadan's central cast, the club bills itself as a society studying the unexplained: ghosts, extraterrestrials, paranormal gifts, urban legends, vanished civilizations, and parallel worlds. That scholarly pretext, though, is only a disguise. The real point is to give Momo, Okarun, and the rest a spot to map out the hunt for his missing kintama and talk over whatever strange events crop up, all without drawing notice at school. Their base is a run-down storeroom tucked at the campus edge, neglected and shabby until the members claimed it.

The club came together during the Onbusuman Arc. Seeing that Momo's friends lacked a steady place to gather intel on Okarun's last kintama, Kinta pitched the notion of a club, and Okarun got behind it with a history-and-culture slant. Momo objected early on but came around once Okarun, Kinta, and Bamora threw themselves into the idea. Once the staff were told, the school handed them deputy head teacher Sanjome as advisor and ordered them to empty out the storeroom for their clubroom.

Things ramped up in the Ultimate Yokai Saga. Through the Kozuka Knives Arc, with the Danmara curse having shrunk Momo, the members dug into fairy lore at the library to undo it, then chased Koki Yukishiro after she came at Momo with a knife. What surfaced was that a teacher whose face Koki had forgotten was coercing her to lift Momo's abilities with a power-stealing kozuka knife. The group set out to tail Koki and snare the culprit, splitting apart when the blackmailer, Murakami, finally showed. He used the Severed Head Dribblers to turn both Koki and Rin into hovering heads, while Okarun and Kinta tangled with Hase and an exosuit-clad Kur. Aid from the pygmies, Mai, and Aira, plus Koki's first use of the Lord of the Flies ability, let them topple Murakami. Later chapters had them collect fresh intel from Manjiro on power collectors, receive the Oni Club for Okarun, and gather once more after hearing of Momo's amnesia from the Shimane events.

The club was started by Momo and Okarun together with Kinta and Bamora, and it was Kinta who first suggested forming it. Aira, Jiji, Rin Sawaki, and eventually Koki Yukishiro pitch in on its activities. The faculty advisor role falls to deputy head teacher Sanjome.