Tsukishiro

Appearance
Tsukishiro is a middle-aged man who usually appears wearing a suit.

History
Tsukishiro is sent to the school by Professor Ayanokōji (Kiyotaka Ayanokōji's father) as the acting director in order to get Kiyotaka expelled and return to the White Room.

Plot
Tsukishiro makes his first appearance in Volume 10 where he appears in the special building, in front of Kiyotaka Ayanokōji and Arisu Sakayanagi while they are talking about the circumstances of the special exam that has just ended. He asks for where the staff room is, then proceeds to introduce himself as the new acting director of the school. After exchanging some words, he starts walking past them and suddenly kicks Arisu's cane. Kiyotaka catches her but gets pushed by Tsukishiro against the wall right after. Arisu asks if acting violently against the students will be a problem, to which Tsukishiro replies that the surveillance camera has been replaced with a false image. He then gives Kiyotaka a message from his father, threatening him to come back. Tsukishiro continues provoking Kiyotaka but he does not retaliate, in case the camera is actually still recording. Tsukishiro then releases Kiyotaka and leaves, announcing that he will formally start working at the school in April.

In Volume 1 of Second Year Arc, he offers a bounty of 20 million private points for the person that can expel Kiyotaka.

In the epilogue of Volume 2 of Second Year Arc, he appears at the epilogue with Tsubasa Nanase asking her to expel Kiyotaka in the next exam so that they can go back to where they belong.

In Volume 3 of Second Year Arc, he is seen discussing with Katsunori Shiba about their plan to expel Kiyotaka. Honami Ichinose accidentally overhears their plans of luring Kiyotaka and some faint information about the White Room. Shiba catches Honami and holds her, but Tsukishiro orders him to let her go. He allows Honami to go but threatens her that if she tells anyone about their conversation, he will personally force a group from her class to retire, which will cause the group to be dropped out. It is also revealed that Tsukishiro has sabotaged Kiyotaka's emergency alert to go off.

Etymology

 * The surname Tsukishiro means "moon" (月) (tsuki) and "castle" (城) (shiro).

Trivia

 * His first name has not yet been revealed.