Hitorijime My Hero centers on Masahiro Setagawa, a hopeless teenager who is bullied by the neighborhood delinquents and forced to run errands for them. He has long accepted that no one will come to his aid, until he crosses paths with Kousuke Ooshiba, the feared “Bear Killer,” a man famous for taking down local gangs and protecting the weak in his own uncompromising way.
A year later, Masahiro and his former friend, Kensuke Ooshiba, enter high school and discover that Kousuke is now their math teacher, turning an old act of rescue into an awkward everyday reality. As Masahiro grows attached to the man he begins to call his hero, Kousuke’s urge to protect him becomes increasingly intense. Their fragile balance is shaken again when Kensuke’s childhood friend, Asaya Hasekura, returns and makes his feelings for Kensuke impossible to ignore, revealing affection that goes far beyond friendship. Against the backdrop of school days, Hitorijime My Hero follows these boys as trust, jealousy, and desire slowly reshape their relationships.