Tadakuni attends Sanada North High School as an eleventh-grade student, initially positioned as the main protagonist before being frequently sidelined in later episodes. He maintains an ordinary self-image, viewing his life as typical in an average town. His physical appearance includes a slim build, average height, black eyes, and short black hair styled in a bowl cut, usually clad in his school uniform. Outside school, he sporadically wears casual attire—setting him apart from friends—and dons a Pizza-Le uniform during twice-weekly part-time shifts. Functioning as the rational counterpoint among friends, he routinely mediates Hidenori and Yoshitake’s chaotic schemes despite vocal disapproval, inevitably participating nonetheless. His creativity surfaces through impromptu storytelling, captivating peers and his sister. Persistent anxiety plagues him over his perceived lack of quirks compared to friends, fearing exclusion due to his normalcy. This ordinary persona evolves into a meta-narrative joke, reducing his screen time as in-universe editors favor "interesting" characters. Paradoxically, this trait propelled him to third place twice in character popularity polls. Background details reveal he attended East Yada Elementary, meeting Yoshitake and engaging in imaginative role-play as "Rubber Shooter." He befriended Hidenori in middle school. His home life features a strained, physically aggressive relationship with his younger sister, whom he avoids. Forced into friends’ role-playing scenarios, he embodies reluctant personas like "Swordsman Tadakuni" or the forgetful "White Knight," protesting absurdity while complying. He displays unexpected skills—parkour and stealth during espionage—contradicting habitual clumsiness evident in mishaps like damaging electronics or spilling paint during cleaning duties. Socially awkward, he harbors an unexpressed crush on Yassan (Literature Girl). At Pizza-Le, he reveals a teasing side toward coworker Nago. Covertly, he exhibits perverse tendencies, including wearing his sister’s underwear—a secret exposed by friends. In spin-offs like AWA Academy and XP4 narratives, fantastical elements augment his character: battle attire (sleeveless coats, fingerless gloves), heightened combat prowess, and "presence concealment" invisibility. These alternate versions also impose an unwanted harem involving characters such as Honoka Kousaka and Chitose Karasuma, starkly diverging from his original portrayal.