Saiki Kusuo

Hairo is the class representative of Kusuo's class. He is a hot-blooded young man who is reliable and gets along well with everyone even towards the outcasts like Kusuo and his circle of friends. Despite finding Kineshi overbearing at time, Kusuo does respect his strong will and how well liked he is in school. But still find him annoying by his wild nature, but somewhat got used to him.

Nendou Riki

For Hairo, Nednou for him is a rival in terms of sports and strengths. Nendou is usually lax in terms of Physical Education but Hairou usually challenges him resulting in Nendou winning.