Ashura Kokuhou is Youta Narukami's best friend, sharing classes and university entrance exam preparations. He sports shoulder-length strawberry blonde hair, usually in a low ponytail, and amber eyes. His go-to outfit consists of a burnt orange shirt layered under a white button-up, paired with black pants and shoes.

A hot-headed streak defines Ashura, particularly flaring up around Hina Sato's pretentious attitude. He snaps at her during their first meeting and stalks off, too irritated to stay. Basketball shaped his past: both he and Youta played for their school team, with Ashura as shooting guard. A traffic accident caused a leg injury severe enough that doctors declared he'd never play competitively again. He still shoots hoops casually, seen playing with Youta just before Hina arrives on the scene.

Ashura primarily supports Youta while expressing deep skepticism toward supernatural claims. His abrupt exit after Hina declares herself the god Odin and predicts the world's end leaves Youta alone for further conversation with her. His name, Ashura (阿修羅), combines kanji meaning "Africa/flatter/corner," "discipline/master," and "gauze/thin silk," while his surname Kokuhou (国宝) translates to "national treasure."