Yugi Tsukasa

As a ghost, Tsukasa appears to be cheerful and extremely childish. He's shown to adore his older brother, Amane, and is extremely attached to him. Due to this childish demeanor, he is often treated like a little kid by Sakura, his assistant, whom he is bound to by contract. Conversely, he is capable of carrying out extreme acts of violence with no remorse. This is shown when he gleefully cuts into a pufferfish just to see what they look like on the inside, despite being warned against doing so. Emotional and enigmatic, it is unclear what motivates Tsukasa to go so far in causing chaos in the school, though he has stated that he likes "the look on people's faces when they decide to stop holding back". He's shown to believe that the rules and order between supernaturals and humans isn't needed, and thinks that supernaturals should act however they want.

Tsukasa is rather manipulative. This is most evident when Tsukasa altered Mitsuba's rumor in order to create the monstrous "Bent-Neck Boy At The School Entrance". He was shown to be very controlling; during the Hell of Mirrors Arc he refused to back down unless someone did as he ordered.

Tsukasa seems to give little weight to the topic of his own murder, often referencing it without hesitation. He derives happiness from seeing the pain on someone's face, calling Amane's face before he killed him his "favorite expression".

When he was younger, as seen in Chapter 78, Tsukasa retained virtually the same personality. He was cheerful and frequently looked for items to cheer his sick brother, Amane, up. However, he is distraught when he hears his brother has not much time to live and sacrifices himself for Amane's welfare, disappearing after this. After his disappearance, and return; their mother momentarily noticed something was off with him, before consulting with the shrine priests. Adamantly claiming that he had been possessed and begging them to bring her real son back, Nagisa went to check on the boy. But before he could receive a response, the boy with the eyes black and empty, points the finger to him and immediately say his wish would come true. The day after, the head priest that Nagisa had hate, ominously died.