Since the beginning of School Rumble, Eri is described to have two natures. Her talents, beauty, riches, athleticism and popularity make her classmates believe that she lives the glorious lifestyle, though in reality, she uses this image to hide her feelings of loneliness and insecurity.
Eri is the daughter of a prominent English businessman, and although she was born in Japan, she was raised in England, therefore having limited knowledge in Kanji. She had been proposed to numerous times but always turned them down, not being interested. People were bad-mouthing her from behind her back on this though, and she was truly lonely until she found herself helping classmate Mikoto with shopping and joining a gathering of rowdy but frank and good-natured family friends.
In time, Eri had a core group of friends and life seemed to be going fine, until she got a crush on her high school's most infamous delinquent, Kenji Harima. It started after an accidental love confession, uttered with such emotion that it shook her. This turns into a love-hate relationship, where Eri has difficulty admitting her feelings and controlling jealousy. It causes a strain with her close friends. When a love rival appears, bitter pride starts to rear its head as we move along the timeline.