She is the daughter of the owner of Copenhagen in Fuyuki. Otoko went to highschool with Taiga Fujimura, keeping a close friendship since then. During the Fourth Holy Grail War, Rider stole a barrel of wine from their bar meant for the Fujimura family, prompting Taiga to track down the culprit out of friendship. Five years before the Fifth Holy Grail War, Shirou Emiya came to start working for them. He took any job given to him, even including working while both she and her father were out sick.