The story's protagonist. Following a terrible accident, he finds himself trapped on the boundary between nightmare and reality.
A mysterious girl who encounters Fuminori while searching for her missing father. Their meeting changes them both in ways neither could have imagined.
Fuminori's best friend. While disturbed by Fuminori's strange behavior, he nevertheless struggles to maintain their friendship.
Koji's girlfriend. A kind woman who tries to help her friend Yoh cope with the changes that have driven her and Fuminori apart.
Omi's best friend. Has feelings for Fuminori, but is finding it difficult to deal with the changes in his behavior since the accident. Unlike the assertive Omi, she tends to go along with what other people want.
Fuminori's chief physician, whom he has visited for regular checkups ever since the accident. She seems to have some connection to Ogai Masahiko, Saya's father.