Tsukasa Honnouji is a male student who transfers schools and forms a close friendship with the protagonist. He stands 149cm tall, weighs 42kg, and has short blond hair, green eyes, and a pale complexion. His typical attire includes his school uniform—trousers and a sweater—often accessorized with belts and cuffs.

Energetic and outgoing, Tsukasa displays comedic cowardice and a self-deprecating "hetare" demeanor. Though athletic and good-looking, his immature, perverted tendencies and nonsensical self-invented phrases hinder his popularity with girls. He craves romantic attention but masks his lack of confidence through bravado and humor. His puppy-like enthusiasm earns him canine nicknames like "Pochi" or "Shiro" from peers.

He harbors deep insecurities about his height, secretly wearing platform shoes for a 10cm boost, and fears inheriting his father's baldness. Rarely mentioned is his family's struggling ice cream shop near the Orifushi sisters' business. Unexpectedly, he excels at sewing and crafts high-quality clothing.

Initially viewing the protagonist as a romantic rival, Tsukasa evolves into a fiercely loyal admirer, constantly seeking validation with phrases like "I’m your best friend, riiiight?" He demonstrates genuine kindness, supporting the protagonist during emotional struggles. Carrying a camera, he photographs attractive girls and idolizes one sister as "Princess Akina."

In the sequel "Dokidoki Full Throttle!", narrative developments suggest potential exploration of his sexuality, including optional same-sex romantic endings with the protagonist.