Arashi "The Predator" Nikaidou
About
She has the 1st grades on 3rd year and has powerful leadership, that she can't only handle most Student Council chores by herself, but also take control most of the school's activity.
She is a bisexual and very aggressive sexually, even to that point that she has over 30 lovers, which has given her the nickname "Predator". However, later in the story she decides to separate peacefully with her lovers and aims to seduce and make Student Council as her harem for time being.
She is actually the cousin of Akito before his adoption by his current parents, and she also knows that Akito is adopted, and decided to support him the way she can. She also knows that Koichiro Shindo is Akito's pen name.
(Source: Wikipedia)