| The subject of this article is non-canonical.|
While created as part of licensed material, it has not been confirmed as part of the "real" Buffyverse.
Mariko was a Japanese girl who was the Slayer during the mid-20th century. She was called in 1956 following the death of Asha Sayre and was killed in the line of duty around 1960. Her Watcher was Kobo.