Rikudou Riin is an undercover cop whose assignment has led him to follow a mysterious and beautiful person who goes by the name of "Joker". He soon deems that Joker isn’t really a villain - but might be a spy, a detective, a mercenary, he/she might be a man or a woman or…both!?

In the Joker Series:
1) Teiou no Niwa
2 & 3) Moon Fantasy
4) Dream Playing Game
5) Green Paradise
6) Sherlockian Computer
7) X no Utagoe (Kai no Utagoe)
8) Final Misson