Haruka Sakuraba, known as Haru, is a female character with long black hair, typically worn loose and reaching her back. Early childhood experiences of mockery by classmates shaped her personality, leading her to develop an arrogant and lonely demeanor. She perceived herself as superior to others, viewing herself as "at the top," using this arrogance as armor against isolation. Her family background includes a strict mother and a father residing overseas, contributing to her emotional distance.

Entering middle school marked a turning point; forming friendships with Ayumi and Shinji significantly impacted her. These bonds gradually softened her defensive exterior, fostering deep care for her close friends. Haruka typically expresses this care indirectly, exhibiting tsundere traits—she alternates between aloofness and genuine concern, particularly within her friend group.