Tengen

Tengen, often referred to as Master Tengen is a supporting character in the Jujutsu Kaisen series. They are an immortal jujutsu sorcerer that remains within their chamber; the Tombs of the Star Corridor, at all times in order to reinforce the barriers that protect both Jujutsu High locations.

Master Tengen is also known as the "Star". At one time they were responsible for preaching the foundation of jujutsu sorcerers and ended up spawning religious groups that worship the Star as their deity.

Appearance
Due to the nature of Tengen's role in the jujutsu world, most people have no idea what they look like. Only those granted permission have seen that Tengen does not quite possess the appearance of a typical human being. Tengen has four eyes with a cylinder-shaped head that features no hair at all, but they do possess a bipedal humanoid body. They wear a simple light-colored robe.

As stated by Tengen, due to Toji Fushiguro killing the previous Star Plasma Vessel 11-years ago and unable to fuse with her, Tengen's current appearance is the result of him having continued to "evolve" past his humanity. This in turn implied that Tengen himself originally possessed a much more human appearance.

Personality
Tengen appears to be a well-mannered, straightforward, and knowledgeable individual with humanity's best interest in mind. They don't seem to mind awkward questions about their experience and is more than happy to help normal jujutsu sorcerers provided the right situation.

Tengen was willing to do all they could to help Yuji and the others stop Kenjaku, but in return asked that two members of his team remain behind to protect them as well. They were stern about this point, but only because Tengen's own safety is the key to humanity's survival.

Abilities
Overall Skill Level: Master Tengen is viewed as an immortal entity and a pillar of security within the jujutsu community, not a fighter who interacts with the everyday functions of the world. Tengen's abilities are essential to the structure and organization of the jujutsu world. They have existed for centuries and are responsible for teaching the foundations of jujutsu that eventually evolved into the modern-day culture surrounding sorcery.

Master Tengen is the most powerful barrier user among all jujutsu sorcerers. They're responsible for the barriers protecting both main campuses of Jujutsu High. Their barrier also strengthens barrier techniques used by school managers, amplifying their ability to cast curtains.

It was thought that Tengen could pose a potential threat to humanity if they evolved. However, since failing to merge with a Star Plasma Vessel, Tengen's sense of self-diminished but they have been able to maintain their awareness with jujutsu and force of will.