Ayakashi is a parasite life force that gives superpowers to its host, taking in return the host`s entire life force. Kusaka Yuu is a student that lost his will to live after the death of a dear childhood friend, until the day a mysterious girl, named Yoake Eimu, appears. From that moment on, his life would never be the same again. Hunted by Ayakashi and their hosts, the power within Yuu awakens and a never ending battle begins.
from ANN

Check out what else is airing this Winter 2007 season.
Découvrez ce que le reste est diffusée cette Winter 2007 saison.

Notes

Genre: Supernatural, Adventure
Not to be confused with Ayakashi (怪～ayakashi～, Ayakashi?) is an eleven-episode anime television series that aired in 2006. The formal title is Ayakashi Japanese Classic Horror.
Adapted from the 2005 adults-only superhuman battle action visual novel game Ayakashi.