1st year, Class 11 15 AB Swimming Club. Previous is Medaka's Student Council

The Student Council Treasurer. She is originally the ace of the swim team, befriending Yakushima (the swim club's captain) and Tanegashima (the swim club's vice captain). All three had an incredible obsession with money for personal reasons and want to gain enough money to fill a pool and swim in it.

When Kikaijima was a child, her father left because the family was in debt, and her mother became sick from working herself in to the ground. All the people that Kikaijima had thought were friends left her because her family had no money. Kikaijima believed that "anyone would be sad if they lost their wallet, but if we died, nobody would care." Medaka corrects her by saying that if they died, she would be sad for them. Afterward, Kikaijima is recruited as the treasurer, and is the only member of the group who is paid for her job.

Though Medaka successfully reforms Kikaijima from her old ways, it still does not keep her from being obsessed with money. Shortly after she joins the Student Council, she charges Zenkichi for accidentally seeing her changing and then again for insulting her and one last time for saying she had a great body. She develops strong relationships with the Student Council members, particularly Medaka and Zenkichi, after being encouraged by Yakushima and Tanegashima to make friends outside of the swim club.