Kurumi

A Steel Angel built by Dr. Ayanokouji and equipped with a Mark II Heart she is awakened by Nakahitos kiss in the first episode and immediately becomes possessive of him while simultaneously pledging her love and service to him. The main female lead and an incredibly wild individual she is overwhelmingly manic when it comes to Nakahito whom she calls quotMasterquot. Whenever her antics become too much one word from her master will make her stop usually. Very protective of her master and her sisters she will stop at nothing to ensure their safety. She is impossibly strong and rather handily defeats all of her opponents due to her Mark II Heart. Although she does her best to follow orders and help out the Kagura brothers her clumsy and ditzy natures prove to be a significant stumbling block. She is the oldest of the Angel quotsistersquot and assumes a fairly typical quotolder sisterquot attitude when speaking with them. Kurumi has pink hair and wears a blue maids outfit with red trim. She sleeps in a loose yukata and generally works her way over to Nakahitos neighboring futon during the night. If he is not present she makes do with a body pillow. She loves bathing and generally does so with Saki since Nakahito usually declines. Kurumi seems to be a bisexual as she loves Nakahito a boy and in the second season Nako a girl. Source: Wikipedia