OVA
Description
Yui Kotegawa is a high school student at Sainan High. She begins as a class committee member and rises to head of the disciplinary committee. Her strict, puritanical enforcement of school rules targets perceived indecency or disruptions, fueled by childhood experiences where boys harassed her classmates. This instilled a strong disdain for male behavior and romantic relationships, which she viewed as inherently shameless.

She possesses long black hair, brown or gold eyes depending on the source, and stands 162 cm tall. Her figure, with measurements of B88-W59-H87, is curvaceous and comparable to Lala Satalin Deviluke's. Yui feels self-conscious about her body, especially when teased by peers like Risa Momioka, and confirms developing early, starting to wear bras in middle school.

Her personality is tsundere, combining a stern, easily flustered exterior with a secretly kind and romantic interior. She frequently reprimands classmates like Rito Yuuki and Lala for disturbances but gradually softens, particularly towards Rito. Her feelings for him develop after he protects her from delinquents, though her inexperience with romance and tsundere tendencies cause her to struggle to admit them. She often denies her emotions, reacts with blushing or anger when teased about Rito, and verbally contradicts her true intentions.

A significant hidden aspect is her fondness for cats, kept secret due to embarrassment. She decorates her room with cat-themed plushies, visits pet stores to observe cats, and molds Valentine's chocolate into cat shapes, revealing a softer, vulnerable side contrasting her rigid persona.

Her development intensifies in the *Darkness* arc. She acknowledges her love for Rito, fantasizing about marrying him, adopting Celine, and bearing his child. Once, under Sugitani pollen influence, she demands Rito refrain from "shameless acts" with others besides her. Later, in Chapter 4 of *Darkness*, she offers herself to him on the condition he limits such behavior to her alone, showcasing her internal conflict between morals and desires. She recognizes Rito's accidental perverted incidents are unintentional, differentiating him from other boys.

Her backstory includes a pivotal childhood encounter where Rito rescued a cat she could not save. She initially did not connect him to this memory, but during an event involving the alien Modorin, she recalls the incident and realizes Rito's consistent kindness, reshaping her view of men and reinforcing her attraction.

In *Darkness*, she becomes vigilant about Rito's interactions with other girls and participates reluctantly in Momo's harem plan. She forms a close bond with Celine; in public, they are mistaken for a family with Rito, fueling her domestic fantasies. Her disciplinary role expands as she partners with Nana to enforce rules using disciplinary armbands. She becomes more integrated into the class, forming friendships with Lala, Haruna, and others.

She has an older brother, Yu Kotegawa, who supports her feelings for Rito, and unnamed parents. Her last name is often mispronounced as "Kokegawa" by characters like Golden Darkness. She cannot swim well, requiring a floatation device, and shares a tendency for overactive imagination with Rito, hinting at deeper mutual understanding.