Shinjo Haruna

She is a childhood friend of Masato and together with her sister Serina, they would abuse him for a long time. She became estranged when she went to Tokyo for university and work.

She returned home after finding herself a rich man she plans on marrying. She has always been famous in her hometown for her beautiful appearance and intelligence.

At the request of Masato's mother, she becomes his tutor. Her twisted nature was not cured during her time in Tokyo, and she takes advantage of her position to abuse and torment Masato to relieve her stress.