I *think* Flandre tells one of the heroines that "one try is 100 yen" so if a western vampire knows the japanese currency, it would stand to reason that it is also de Gensoukyou currency.
I *think* Flandre tells one of the heroines that "one try is 100 yen" so if a western vampire knows the japanese currency, it would stand to reason that it is also de Gensoukyou currency.