Ghost Slayers Ayashi

is a Japanese anime series, created and written by Shō Aikawa and produced by Bones. Directed by Hiroshi Nishikiori, it featured character designs by Toshihiro Kawamoto and premiered across Japan on October 7, 2006 on TBS. While originally scheduled to air for 52 episodes, the series' length was shortened to 25 due to its low ratings and ended its run on March 31, 2007.

Plot
In the year of Tenpo 14, Yoi, monsters from another world attack Edo. Those who fight against them are members of Bansha Aratemesho, an organization dedicated to destroying the Yoi under the public facade as a group to study foreign books. The warriors in the organization are called Ayakashi.

Other Sources

 * Anime