Satsuki Uruma

Satsuki Uruma is a missing friend to Kozakura and mentor/private tutor to Toriko Nishina.

Appearance
Satsuki is described as a tall woman with pale skin, a long stark black hair, wears thick-rimmed glasses and has a nasty look in her eyes. When she appeared in File 4: Time, Space, and a Middle-aged Man only as a trap made for Toriko and Sorawo, her eyes were incredibly blue.

Personality
Satsuki is known to be charismatic and a "natural born alpha female", being able to charm everyone who came near her. She is noted to have a habit of treating people like tools, rather than as people, and when people ceased to be useful to her, she would lose interest in them. Her skills in seduction were not reduced upon vanishing into the Otherside, as shown in Volume 7, and Toriko notes that when Satsuki tempts someone, that person tends to become dizzy from her temptation.

Background
Satsuki was originally Kozakura's friend, and were in the same class in university. Before she invited Kozakura to do a 'collaborative research' project with her, she had already known the existence of the Otherside. Satsuki had made contact with the DS Lab some years ago, claiming to have a safer way of going to and from the other world, bring back UBL artifacts with her. With her experience and knowledge of the Otherside, DS Lab invited her as a researcher. She was also recruiting promising individuals to expand her investigation of the Otherside. As part of this recruitment scheme, she would give "tests" to those she took an interest in, ranging from giving them cursed objects to see how they would handle them, to simply taking them directly to the Otherside.

Satsuki's disappearance continues to be a mystery as she was not the type of person to discuss future plans and all her research notes were encrypted by her back at DS Lab. In Volume 7, it is suggested that she had been "swallowed up by the Otherside, never to return".

Abilities
Satsuki's incredible skill of seduction and charm seems to have been her greatest strength. It is unknown whether she was a Fourth Kind, or purely human, or perhaps she even became a phenomenon that merely took her name and shape. She seems to have the ability to selectively appear only to certain people, primarily Sorawo, and on one occasion, her reflection appeared in a Mirror Cube. She also exerted some kind of influence on Toriko in Volume 7, which nearly led to Toriko vanishing entirely. When she was summoned at her funeral in File 23, Sorawo observed her as a human-shaped hole leading to the Ultrablue, and looking directly at her caused Runa Urumi to fall unconscious.