Title: Guin Saga, グイン・サーガ
Airs: 04/05 23:29

Total Episode Count: 13 (?)

Animation Studio: Satelight

Summary from ANN:
Somewhere in the Middle Country,there roams Guin,a mysterious warrior who is revered by the people. Wearing a leopard's mask,he has lost all the memories he held except his combat instincts and the word "Aurra". When the people of the Middle Country is attacked by demonic creatures,it is up to Guin to save them.
The ancient kingdom of Parro has been invaded by the armies of Mongaul, and its king and queen have been slain. But the "twin pearls of Parro," the princess Rinda and the prince Remus, escape using a strange device hidden in the palace. Lost in the Forest of Rood, they are rescued from Mongaul soldiers by a strange leopard-headed man named Guin, who has no memories except for the word "Aurra."

note: Music for this series is by the legendary Uematsu Nobuo, known for his extensive work with SquareEnix's Final Fantasy games. The novel series is at 125 volumes (yes 125 volumes) and has 21 volumes of side stories.