You Come Without a Trace and Leave Without a Sign

[Twin male leads versus a big, cheerful girl heroine? What, I have to choose one? A gentle, outgoing exiled crown prince who’s a master flirt, or his aloof, proud younger brother, a stunning courtesan who disguises himself as a man? Only a fool would choose. I want them both!]

The male lead is an envoy from beyond the heavens, who came to Earth as one of a pair of twins. He secretly establishes an assassination organization, meets the heroine, and joins forces with her to dismantle the monarchies of three kingdoms from within. Together, they build the first great nation united in harmony. Afterward, he vanishes without a trace into the long river of history.