TV-Series
Description
Shikkokumaru is the Ancient Yo-kai Hero form Jinpei Jiba assumes using the Majin Watch. This transformation constitutes an upgrade beyond the anime-exclusive final form Black Cat, which Jinpei accesses via the UR Watch inspired by the Yo-kai Mikettio. Shikkokumaru manifests as a direct evolution of Earth Walker NOA, who absorbed power from the reborn Yo-kai World within Earth Walker.

Physically, Shikkokumaru presents a cat-like Yo-kai Hero silhouette with a dark gunmetal grey body featuring black fiery spots and a yellowish/white whisp on his forehead. His cyan blue eyes possess dark blue pupils encircled by black raccoon-like markings. The design incorporates dark gunmetal grey ears displaying purple inner sections, whisp-like hair protruding upward at the back, and two flame-like tails shifting from purple bases to dark gunmetal grey tips. A cyan blue headpiece encircles his head, covering the sides. His attire includes a black and purple leather jacket adorned with collar pins (including the letter 'Y'), a greyish-blue undershirt, black pants with grey flames at the ankles, and black shoes showcasing white flames and tongues with grey soles. Cyan blue gloves with blue fingers and white knuckles complete the ensemble.

Shikkokumaru utilizes specialized attacks: Ambush in the Dark Night (闇夜の奇襲), Ruin of the Dark Night (闇夜の破滅), Grand Order Earth Break (グランドオーダーアースブレイク), and Final Black Lightning (ファイナル黒い稲妻). Final Black Lightning clears all targets and increases effectiveness during fever states in game adaptations.

The character debuted in anime episode YG057 when Earth Walker NOA, overwhelmed by uncontrollable power from the Yo-kai World during the summoning of Classic Yo-kai, transformed into Black Cat. Master Nurari provided the Nura Kimono, enabling the shift to Shikkokumaru to control this power. Zazel proposed "Black Cat NOA" as a name, while Jinpei suggested "Makkurokuromaru" due to the form's resemblance to Kengo Benimaru. Mataro Tamada rejected both, deeming them unsuitable for a hero, and designated him "Shikkokumaru".

The name derives from "shikkoku" (漆黒, jet-black) and the suffix "maru" (丸), likely referencing Kengo Benimaru. A distinctive rock and roll-themed transformation song accompanies the change: ♪Black Cat! Into the jet black! Shikkokumaru!♪ (♪ブラックキャット! イントゥ ザ ジェット ブラック!漆黒丸!♪). Narratively, Shikkokumaru confronts threats from unstable Yo-kai World energies. Game transformation sequences depict Shikkokumaru emerging directly from Earth Walker NOA, establishing him as Earth Walker's game-exclusive final form, contrasting the anime's progression through Black Cat.

Shikkokumaru remains the sole Majin Yo-kai Hero depicted in Y School Heroes: Bustlin' School Life. His signature quote is "Well then. Dyed in my jet black! Shikkokumaru!" (俺の漆黒に染まれ! 漆黒丸!), emphasizing his thematic association with darkness and controlled power.