He is a delicate, soft-spoken boy who takes care of his younger brothers to help out his busy parents. He joins Akito's karate club at school because he wants to become strong and cool like Akito. However after their first training session which was too tough for him, Shota becomes sick and misses a day of school, breaking his never-absent record.
Akito mistakenly believes that Shota wants to quit the karate club, but is afraid to say so. So Akito tells Shota to quit, which makes Shota feels like he's been kicked out of the club, and it depresses him. He becomes further depressed when Mr. Sengoku, his homeroom teacher, doesn't even remember that Shota is in his class.
Despairing at feeling rejected by the two people he admires the most, Shota starts believing that he's invisible. So Shota writes a 2-page letter to Mr. Sengoku and locks himself up in an old storage shed on campus which was the karate club's meeting place. After going missing for a whole day, he is discovered by Sana and Akito, who, while trying to rescue him get their heads stuck in the window, but all three are eventually found and rescued. After they are rescued, Akito tells Shota that they are alike, because Akito also felt invisible and wanted to die when he was having a tough time with his family.
The first page of Shota's letter mentions Akito, which Mr. Sengoku tries to use to get Akito expelled from school, blaming Akito for making Shota suicidal. But Fuka finds the second page of the letter Mr. Sengoku deliberately hid, which blames Mr. Sengoku for ignoring him. Mr. Sengoku is shamed by this revelation and eventually resigns from school.
