Atsushi Ikeda, known for his compassionate nature, takes care of abandoned animals and provides them with shelter in his own home. One night, he finds an injured high school student, Riya Narukawa, with a violin outside his door and decides to take him in. Riya, a fierce young man, wakes up with no recollection of why he was unconscious there, as memory lapses are common for him.
The next day, Riya experiences a headache while playing the violin for Atsushi and confesses to having a deceased brother's spirit within him, forcing him to play. Atsushi is shocked, but soon discovers that Riya is a gifted violinist and the son of a famous musician. He also learns that Riya has a multiple personality disorder, which causes him to believe that his younger brother's spirit resides within him. As Riya struggles to understand his psychological issues that stem from societal pressures and expectations placed upon his talent, he begins to realize the importance of Atsushi's presence in his life.
