Kamen no Maid Guy EP12 - Farewell, Dear Maid Guy

Kogarashi and Fubuki battle a female Masked Maid with shark teeth and powers rivaling Kogarashi, hired to assassinate Naeka. This maid, hired by a wealthy man attending Naeka's Grandfather's 70th birthday party, appears to be of the same clan as Kogarashi and reveals him to be hundreds of years old.