Dagon

Dagon is an antagonist in the Jujutsu Kaisen series. He was an unregistered special grade cursed spirit aligned with Mahito, Jogo, and Hanami. Dagon was born from the fear of water-based natural disasters and existed as a cursed womb until he evolved during the Shibuya Incident.

Appearance
As a cursed womb, Dagon had an appearance similar to an aquatic animal like an octopus. He's bright red with a circular-shaped head, big round eyes, and striped tentacles around his mouth opening. Dagon had two muscular arms with four fingers and a caterpillar-like body. He normally covered himself with a white cloth draped over his head and back.

In his evolved state, Dagon had a much taller, humanoid shape, similar to Hanami. His head changed to a shape reminiscent of an octopus with black dots on the top. He was mostly red, including the outer portions of his arms, thighs, hips, and chest. The inner sections of those areas of his body were tan. His midsection was black and he had wings on his lower back that allowed him to levitate.

Personality
In his cursed womb state where Dagon was essentially an infant curse, he was very docile, especially compared to Jogo and Hanami. He would remain on the sidelines through most of the operations and simply maintained the domain in their group's hideout. Dagon would devour people when called upon but wasn't nearly as active as his allies. He was most comfortable around his allies and appeared very shy and nervous when alone.

Dagon would silently follow his friends while in their company. Despite being capable of human speech, he only communicated through noises like "bwoo-hoo" and didn't participate in any conversations. However, Dagon cried out for help and called for his friends by name when he was in trouble. When he realized Hanami was already gone, Dagon was infuriated to the point where pure rage drove him to evolve from a cursed womb into a full-fledged cursed spirit.

As a powerful cursed spirit, Dagon gained a much more aggressive personality and took pride in his strength as a curse, far more reminiscent of Jogo, Hanami, and Mahito. His overall intelligence grew a great deal, so he spoke regularly and used tactics to overcome adversity.

Dagon's anger over Hanami's demise made him resentful of his enemies and didn't take kindly to being referred to as simply "cursed spirit", emphasizing that he and all his allies chose to bear names. While he did recognize that Naobito was a powerful opponent, he mocked Maki for being a weak and was irate when she taunted him back after surviving his attack.

Dagon ultimately underestimated his human opponents and tried to resist having his pride crushed when he was bested by Toji Fushiguro, a human with no cursed energy at all. Dagon admitted that he needed his domain's guaranteed hit to have any chance of winning and attempted to buy time. Even at the very end, Dagon tried to resist his fate, claiming the fight wasn't over just before being exorcised.

Abilities and Powers
Overall Skill Level: Dagon is a special grade cursed spirit with massive amounts of cursed energy and the ability to manipulate water. While in his weaker cursed womb form, Dagon can easily dispatch numerous non-sorcerers simply by devouring them. He can cast a domain and manifest a vast amount of water while in this form as way.

Dagon in his fully released form is far more powerful and can rival the strength of his special grade allies. His strength was high enough to go toe-to-toe with Zenin Family head, Naobito Zenin. Using his domain, Dagon can overpower a group of high ranking jujutsu sorcerers. Naobito, Maki, Nanami, and Megumi together could not defeat Dagon inside his domain despite working together.

Battles & Events
Shibuya Incident Arc
 * Jujutsu Sorcerers vs. Dagon
 * Toji Fushiguro vs. Dagon

Trivia

 * Dagon's appearance is most likely a reference to the works of H.P.Lovecraft.
 * Dagon's name originates from the ancient Mesopotamian and ancient Canaanite deity. A long-standing association with a Canaanite word for "fish", perhaps going back to the Iron Age, has led to an interpretation of this deity as a "fish-god".
 * Dagon is also a short story by Lovecraft about the eponymous fish god.