Shun Futami is a 17-year-old high school sophomore standing 178 cm tall, weighing 68 kg, with a birthday on July 7th. Athletic and a member of his school's handball club, he regularly engages in fitness activities. His interests include running and shoe window-shopping, though he dislikes reading.

Presenting a cool, stoic exterior, Shun frequently displays clumsiness in everyday situations. When his mistakes are noted, he habitually insists they were made "on purpose" to maintain his image. This gap between his cool appearance and his honest, blunt personality leads others to perceive him as cute—a description he strongly dislikes.

He owns a dog named Sakura and is notably forgetful, sometimes resulting in awkward or humorous incidents. His relationships include his older sister Asami, who runs Mawarimichi Cafe. There, he meets Hayate Ichikura, whom he respects and addresses as "Sensei" or "Hayate-san" for academic assistance. During walks with Sakura, he encounters Souma Shiki in a park, initially mistaking Souma for someone younger; he interacts casually with Souma, using no honorifics. On another park outing with Hayate and Souma, he meets Motoharu Igarashi, remaining informal but admiring Motoharu's work with the band Onizero, which Shun favors.

Shun also participates in group contexts, joining Sora's Team through Souma, where he assists other heroes when needed.