Sōma Mizuno, a 25-year-old firefighter at Sakuragaoka Fire Station, stands at 186 cm with a muscular build suited to his profession. Born May 5, he has dark brown hair and striking blue eyes. His life intertwines with childhood friend Ryo Fujihashi after he saves her from an apartment fire, providing her shelter and finally confessing feelings he concealed for years. Though initially seen as playful and flirtatious, his bond with Ryo reveals a steadfast, earnest side, marked by direct communication and unwavering commitment to her safety.

Their relationship encounters strain when Ryo’s ex-boyfriend reappears, testing Sōma’s emotional resilience. He balances these personal challenges with his demanding career, supported by colleagues like Yuki Izumi and mentor Jun Hase, who underscore his teamwork and dedication. Outside work, he enjoys basketball—a holdover from his high school years—and quiet moments spent reading, blending physical vigor with thoughtful introspection.

His growth lies in shedding superficial impressions to embrace vulnerability, transitioning from a charming exterior to a partner who prioritizes reliability and open dialogue. This evolution reflects both his protective instincts as a firefighter and his deepening emotional maturity, anchoring his identity in both personal loyalty and professional integrity.