Fujio Uzaki is Tsuki Uzaki's husband and father to Hana, Yanagi, and Kiri Uzaki. Hailing from Japan's Kansai region, he proudly maintains its cultural ties, consistently speaking the Kansai dialect and urging his children to do the same. Only Yanagi embraces it fully; Hana abandoned it after childhood teasing, while Kiri perceived Fujio's push as forced cultural imprinting.

Standing 170 cm tall with a muscular build at age 46, Fujio sports short black hair parted right, blue eyes (brown in anime adaptations), and faded chin hair. His typical attire includes dark long-sleeved shirts and light-colored pants. Youthful depictions show him clean-shaven with longer hair, bearing resemblance to Shinichi Sakurai.

As a sports club fitness instructor, Fujio mentors Shinichi Sakurai, admiring his training dedication. Unaware Shinichi is Hana's romantic interest, he confides in him about concerns over his daughter dating an unnamed senior—creating dramatic irony. This culminates at a Christmas gathering where Fujio discovers Shinichi's identity, sparking initial distress but eventual acceptance fueled by preexisting respect.

Fiercely protective of his family—especially his daughters—Fujio exhibits vivid emotional swings from exuberant joy to intense nervousness. He relishes lighthearted chats but often irritates his children by being overbearing. Openly affectionate with Tsuki, his flirtatiousness sometimes embarrasses the family. Fujio shares a teasing rapport with Yanagi and supports Kiri through athletic insecurities despite occasional rebelliousness.

Fujio moved solo from Kansai to Tokyo to study physical education, achieving his goal to become a fitness instructor. His character evolves as he reconciles overprotectiveness with Hana's autonomy amid her relationship with Shinichi. Key turning points include witnessing Hana and Shinichi hold hands and gradually acknowledging Shinichi's integrity after initial turmoil.