My sister is a villain in an eroge?!

Nathaniel awoke in an unknown room and body. Not only that, but a system instructed him to steal everything from the protagonist. But he didn't care; the important thing was... Is his sister also a transmigrated? And now they have to work together to conquer heroines while avoiding death as villains?! ---------------------------------------------- Warning advice: Contains incest the cover is not mine, if the creator wants me to delete it I will do it. Support me on: Ko-fi. com/harvier