The protagonist Saiya was born in the Sai family of the Prontela Empire on the Cloud Road. The Sai family is the largest family in the entire Cloud Continent. The reason is that every generation of this family has famous people, including swordsmen, archers, merchants, mages, and priests. But the whole family starts from the first place. Until now, no one is a thief, no, not one. For such a big family, this kind of profession that hurts people in the dark and uses poison is a shame. Even the most noble knight may be assassinated by a newly minted thief with poison, but the protagonist Saiya is an assassin, yes, an assassin. . . . . .