Sōma Shiki, a 19-year-old vocational design student frequently mistaken for a high schooler, carries a youthful appearance defined by magenta-dyed hair, matching magenta eyes, three piercings on his left ear accompanied by a triangle-shaped tattoo behind it, and one piercing on his right ear. He resides with his older brother Sōta Shiki, who works at a company alongside Takayuki Mima.

Employed part-time at Mawarimichi café, Sōma learns cooking skills under his boss Asami Futami. His personality embraces an accepting and positive outlook; he laughs off personal clumsiness instead of feeling embarrassment, yet privately wrestles with insecurities about lacking adequate "weapons"—meaning skills or confidence—to chase his design career ambitions.

Sōma's relationships unfold through chance meetings: encountering Hayate Ichikura outside the café and addressing him as "Hayate-kun," meeting Shun Futami while photographing in a park and calling him "Shun," and being introduced to Takayuki Mima while collecting his intoxicated brother, referring to him as "Mima-san." Later, he bonds with Motoharu Igarashi during a group outing with Hayate and Shun, solidifying their connection at a movie theater while using "Motoharu-kun."

Across official media, such as the spin-off "Petit Cool Doji Danshi no Hitokoma," his growth centers on navigating vocational hurdles, strengthening friendships within a circle of similarly awkward young men, and incrementally facing self-doubt through workplace exchanges and shared activities.