Ouka is teenage girl with a well endowed figure and is described as "perfect" by Kanade Amakusa. Ouka has long, dark-brown hair that goes past her hips and a pair of round light purple eyes. She wears a pink headband with a big bow on the left side of her head. She has been seen in two outfits; the standard girl's uniform, and a long-sleeved purple sweater with pink colored skirt. When she wears the Academy's uniform, she unbutton the bottom part of her shirt, revealing a bit of her stomach also wears a pair of brown boots.
Cheerful, hyperactive, airheaded and sometimes a happy-go-lucky girl. However, despite that, she is also very pure as shown when exposing her underwear makes her embarrassed and when she recalled her mother's words of only crying in front of the man she loved.
She has a tendency to refer people with cute nicknames like Kanade as "Amacchi" and Furano as "Furanocchi". It is revealed that she is on good terms with Konagi, a girl who is placed as the third in the popularity rankings, despite being in the Reject Five herself.