Yūkiri The Sea Demon

Yukiri was once a human a long time ago, in the Heian Era of Japan, but not even he remembers this time.

Yukiri is responsible for granting Shizuko Yamamura her mental powers, in exchange he asked for a favor, a daughter, Shizuko then made a pact with Yukiri to generate Sadako Yamamura, Yukiri is also responsible for corrupting Sadako's soul and transforming her into an Onryō after her traumatic death, granting her the ability to curse, despite this Sadako never had knowledge about Yukiri and his actions, he kept it a secret.

The spirit of the paranormally-powered girl from the American adaptations of The Ring, Samara Morgan, is actually Yukiri's attempt to reincarnate as a human again; conveniently, Samara, Mahito's failed human form, and Sadako, Mahito's daughter, had very similar stories.

Yukiri didn't count on her form as Samara dying and becoming a spirit. After Samara's spirit is purged, Yukiri returns to being a demon.

Yukiri (written: 夜霧) is a Japanese name, which can mean "night fog"

Over 1,000 years, I have been alive since the Heain Era

Masculine
He/Him

Yukiri can change her appearance at will but manifests as a thin woman with long hair, similar to that of her daughter, Sadako, empty, completely black eyes, pale blue skin, black claws on her hands and feet and a body covered in bandages that wrap around her like clothing.

Yukiri is sadistic, he likes to play with humans and do surreal experiments with them, despite this, he is cautious in his actions and does everything so that they do not notice his participation in the story.
Yukiri genuinely enjoyed Shizuko Yamamura's company.

Yukiri likes to think that if he were human, he would be a good father to his daughter, but understands that as a demon he sees Sadako as just a piece in a greater plan, despite harboring concern for her, demonstrated when he turns her into an Onryō so that she can avenge her unjust death.
Yukiri also feels deep sadness for the memory of Shizuko, he considered her his promised spouse, and wishes he had been able to prevent her suicide.

Yukiri calls the process of transfiguring a human's soul "raising their perfection."

Inert Transfiguration: With just a touch, Yukiri is able to manipulate souls, forcing the victims' physical bodies to change as well. He uses this to transform humans into monsters and vengeful spirits, as well as granting powers to normal humans. Yukiri can also use Transfiguration to alter and preserve the form of his own soul, being able to change shape as he wishes and regenerate.

Mental Manipulation: Yukiri is able to put any information he wants into someone's mind, images, sounds, tastes, entire scenarios, any information

Water Manipulation: Yukiri is able to manipulate a massive amount of water and do whatever she wants with it, it is a limited but versatile ability, in addition, the seas of Oshima Island are her home and she rarely leaves there or manifests in a corporeal form.

Soul multiplication: Yukiri is able to multiply a soul by generating clones or aberrations of multiple members, he can obviously also do this to himself.

Pacts: Yukiri is able to generate a binding agreement between himself and a human with a simple handshake, the pact can have numerous clauses, an example was the birth of Sadako by Shizuko in exchange for powers

True form: Yukiri can transform his physical form at will but no matter how many times he alters the essence of his soul he never feels complete, only when he assumes this form, a thin demonic being with black skin with a melted appearance, a black liquid roams throughout his body covering his eyes, his teeth become even sharper forcing his mouth to be wider, large horns and huge black claws, he becomes more resistant and powerful.

Arsenal: Yukiri is able to store all the humans he has transfigured into creatures, and summon them whenever he wants. There are a wide variety of creatures, Yukiri's mind has no limit to creativity.

Playful, Seductive, Manipulative, Smiling, Provocative