Karen Hakuba (白馬かれん) ,also known as Haku (白), is SHSL Private Investigator at the rebuilt Kibougamine Academy. She works as an in-man for Future Foundation and is the girlfriend of Yoshito Matsuo.
Karen is of average-height for her age, has pale skin, black hair and dark eyes. As a child she was overweight due to her tendency to binge-eat. During the Tragedy, and as she got older, Karen lost a significant amount of weight.
Prior to and during some of her attendance at Kibougamine, Karen had no interest in maintaining her appearance; not even having used so much as a hairbrush before. After revealing to Kaoru Akita that she only had a total of three outfits, he took her out and greatly expanded on her wardrobe.
After this, Karen began taking further pride in her appearance out of a desire to appeal to Yoshito Matsuo. Karen prefers to wear black leather and dark-coloured outfits.
Karen has a very guarded disposition and often reacts stiffly to extemporary conversation.