Какіо Хадзукі

A female fighter and expert in martial arts, who is also the college's physical education instructor. There are several personalities within her, from a mischievous child to a brave fighter. When Hazuki foolishly tested a memory-erasing machine and her many personalities were programed into its computer, Sorata went in to save her by going in himself. Whilst Sorata went in search of the Kakio family treasure, he discovered Hazuki in what seemed to be a disabiliting, emotional fractured and disassociated state where she was forced to be completely cut off from the rest of the world.

By gaining her trust and promising never to leave her as her family had, Sorata was about to uncover the secret and truth behind the Kakio family treasure (Steals 18 to 20). She has a habit of appearing in the strangest places (bathroom, washing machine, etc) while wearing only a kinbaku. (Source: Wikipedia)