Haku, Sanshi

Sanshi is the Nyokai of the black Kirin Taiki. During the many years following the disappearance of Taiki's ranka she searched for him relentlessly while everyone gave up, and finally was able to help retrieve him from the human world. She hasn't left his side since, following him even when he returned there.

[Spoiler] After Taiki's horn was cut, her source of food (the chi of a kirin) was cut as well and she started to go insane, gradually killing those around Taiki as she viewed them as "threats". [/Spoiler]