Youmu Konpaku from Touhou Project

Species: Half-human half-ghost
Ability: Swordsmanship
Residence: Hakugyokurō
Theme Song: Hiroari Shoots a Strange Bird ~ Till When?
Stage 5 boss and stage 6 midboss, in addition, she is a playable character in Touhou 7.5-9, and 10.5 as well. Youmu is the gardener of the netherworld pagoda, Hakugyokuro. She comes from a very rare breed, the half-ghosts; in this strange combination, the human half and ghost half exist in physically separate bodies, but are always close by one another. Youmu is very young for a half-ghost, under 60 years; her exact age is unknown. While straightforward, focused and loyal to her mistress, Yuyuko, Youmu is still rather immature, and tends to be a target for teasing by the other girls of Gensokyo (particularly her mistress Yuyuko). Paradoxically, she is afraid of ghosts (the imaginary sort). Her talents are swordsmanship and speed. In the games, she is characterized by creating powerful danmaku with her sword slashes, and slowing time (this is not due to magic as one might expect, but because of time slowing around her body as she goes past at unimaginable speeds).