TV-Series
Description
Arashi Nikaido is a prominent character in the anime OniAi, serving as the student council president at Saint Liliana Academy. She is a third-year student who stands out immediately due to her distinctive and flamboyant appearance. Arashi has long red hair which she typically wears in a high ponytail, and she possesses heterochromia, a condition where her eyes are of different colors. She is frequently seen wearing a black eyepatch over her right eye and is seldom without a real katana, which she carries casually around the school and the dorms.

As the student council president, Arashi is incredibly capable and intelligent, holding the highest grades among all third-year students at the academy. She is a powerful and effective leader, able to handle the majority of student council duties on her own and take control of most school activities with ease. However, her competence is matched by a personality that is loud, boisterous, and overwhelmingly flirtatious. She is an aggressive and unashamed bisexual who frequently makes sexual advances towards both her female and male peers. Her behavior has earned her the reputation and nickname of The Predator, as she openly claims to have had over thirty lovers.

Despite her predatory reputation, Arashi is not portrayed as a malicious character. Her actions are typically played for comedic effect, and she can be surprisingly considerate. For instance, when caring for a sick Akito, while the other girls attempted elaborate and romantic methods, Arashi simply changed the warm towel on his forehead for a fresh, cold one, an act he later cited as the most effective. She has a well-known signature laugh, a distinctive "KA-ka-ka" that punctuates her speech, and she often gives herself outlandish, self-aware explanations for her quirks, such as claiming her eyepatch and golden eye are the result of eighth-grade syndrome.

Arashi's primary role in the story is as a resident of the student council dormitory and a rival to Akiko for the affection of Akito, the male protagonist. She is a key member of the harem of unique girls who live with him. Her initial motivation appears to be the pursuit of pleasure and the collection of new romantic interests, which leads her to declare her intention to turn the entire student council into her personal harem, with Akito as a prime target.

Her key relationships are central to the plot. She has a close, though often chaotic, bond with the other student council members, including Anastasia Nasuhara and Ginbei Sawatari. Her rivalry with Akiko Himenokoji is particularly notable; Arashi often teases Akiko by calling her her underground lover or sex slave, much to Akiko's frustration. In a significant turn regarding her background, Arashi is revealed to be a cousin of Akito and Akiko before Akito was adopted into the Himenokoji family. She is also the only person who knows that Akito is the author behind the pen name Koichiro Shindo, a secret that gives her a unique connection to him.

While Arashi is largely a static, comic relief character whose outrageous behavior defines her role, she does exhibit subtle development. Her aggressive pursuit of "lovers" evolves as she decides to peacefully break up with her many partners to focus her efforts on seducing the members of the student council, suggesting a shift from mere conquest to a desire for a more meaningful, if still unconventional, connection. Furthermore, despite her lascivious claims, when she wins a date with Akito, she spends the time engaged in a chaste, elegant tea ceremony, revealing a more refined and gentle side beneath her predatory exterior.

Arashi's notable abilities extend beyond her academic and leadership skills. She is a skilled swordswoman, proficient enough to be seen carrying a katana as a matter of course. Her self-proclaimed title of The Predator also speaks to a different kind of skill: a high level of social and sexual charisma that she wields fearlessly.