V------------V G-----------PG----------PG13-----------R------NC17Why: V, MO
Two words: Monster Movie [nasty mostly undead monster movie, actually]
Well, ok, maybe more then that. Hikage, you see, is a ninja and his boyhood friend, Marou, seems to not only be in league with a group of nasty monsters, but seems to be the king of these creatures, a being known as Kikuga no Miko. Hikage takes it upon himself to chase Marou to a final confrontation.
Hikage confronts many evil Yoma creatures, including Majuumi no Miko, a Yoma in the form of a horse which control the Yoma of the sea and Shiratsuyu, a Yoma in the form of a huge snake, who controls the Yoma of the land.
Along the way, a ninja girl named Aya attaches herself to Hikage. The irony is that Hikage knew another Aya who killed herself.
As far as ninja, monster, nasty creature movies go, say comparing it to Ninja Scroll, Yoma has a better story. The monsters are true monsters, and the "tender" bits are well done.
On a historical note. The person Nobunaga Oda, while having only a minor role in this piece of Anime, plays a big part in Yotoden: Chronicle of the Warlord Period. In addition, the Marou creature featured at the end of Yoma bears a striking resemblance to the Wolfen creatures in Shadow Skill.