Yuko Sugino is a close friend of Tatsumi Sendou. Initially shy and introverted, she hides long-held romantic feelings for Tatsumi, her timidity preventing their expression. Over time, Yuko experiences notable growth. She gradually gains confidence in herself and her interactions with others. This personal evolution builds to her openly confessing her feelings to Tatsumi. Beyond her romantic role, Yuko demonstrates consistent kindness and selflessness. She consistently puts the well-being of others, especially her friends, first. Her supportive nature drives her to actively help friends confront antagonistic forces. Yuko transforms from a reserved individual into a more assured presence within the group dynamic, marked by steadfast reliability and emotional resilience.