Hiroka is Yukisada's classmate during their first year of high school. While thought to be very beautiful, she acts cold towards others so most people leave her alone; she was given the nickname "Tundra Queen" due to her standoffish personality. During her junior-high school life, she was bullied constantly and even did not go to school for a year because of it. In high school during exam time, she gets help from Yukisada's older brother Nao as a tutor to go over things she learned in school. Some of her classmates from her junior-high still attempt to tease her, though Yukisada does his best to encourage her and help to build back her self-esteem. Due to this, Hiroka becomes quite attached to Yukisada and even one day confesses her love to him; eventually, Hiroka shares her first kiss with Yukisada. Hiroka is also very good at cooking.