High school freshman. 193cm / 91kg. He left his family home and transferred schools following a violent incident involving his father. However, he ends up being haunted by a ghost named Kabuto at his new apartment. As he spends time with Kabuto, they begin to need each other deeply. He is cold to everyone except Kabuto, often saying things like "Shut up" or "Yeah, whatever." Only to Kabuto does he show a smile, saying things like "Yeah. You're right."

He transferred schools to follow Tsubaki. His stated reason is simply "I just want to be friends," but his true intentions are hidden... He is trapped in the past, and it is related to Tsubaki. He calls Tsubaki by his first name without honorifics and feels a sense of wariness toward Ibitsu.

High school freshman. 179cm / 68kg. A classmate at the same high school who approached Tsubaki out of interest in the "Monster." He is an existence that stands apart from others in a different sense than Tsubaki. Mysterious and inscrutable. His hobby is observing people he finds interesting.

High school freshman. 168cm / 58kg. The ghost haunting Tsubaki. Tsubaki calls him "Kabu." Cheerful, brave, and possesses a strong sense of justice. He was apparently killed while trying to help someone else. Despite being a ghost, he acts bright and energetic. Generally, no one can perceive him, but Tsubaki, whom he haunts, can see and talk to him.