Kaname Kenjou

Kaname is a very domineering, forceful, and devious girl who is also on the student council for Spica. She often likes to take matters into her own hands when Shion - or Kaname herself - doesn't get her way. Kaname apparently considers herself irresistible and has no interest in objections to the contrary. Much like Amane, her appearance and personality make her seem more masculine than feminine. She is later revealed to be jealous of Amane, who has effortlessly defeated her at everything since she first came to Spica. It is also suggested that she felt an attraction to Amane at one point, or at least that her self-comparison to Amane has become a central factor of her life.

Her main friend and ally is Momomi Kiyashiki, who is very much like Kaname in personality. They share a sexual relationship and seem to be in love with each other. Together, they are the closest thing to antagonists in the story. Ironically, since Kaname is usually the instigator of their plans, she also seems to possess the strongest sense of personal honor, desiring victory through achievement, not forfeit.

(Source: Wikipedia)