Cofun Gal no Coffy: Okehazama no Tatakai

Coffy, Daniel, and Okehazama-sensei enter a forbidden room behind Tumulus High School and emerge in Japan's distant past. Their accidental time slip places them in the middle of the Battle of Okehazama, where Okehazama-sensei somehow becomes entangled with the fallen soldiers. To get home, the group must survive their absurd encounter with history and discover how their teacher fits into the famous battle.