A Happy Ending for Villains

Sasha is the cunning villainess in the novel "War Wagon of Fire" who uses the evil sons of the Serpente Family to plunge the Xerkesia Empire into chaos. But when the reader wakes up as a younger version of Sasha who's trapped in a hidden corner of the Serpente manor with the Serpente children, she's baffled because this was never mentioned in the novel. The children's uncle claims it's only for a week to protect them from the plague that killed their parents, but when a week passes without anyone letting them out, Sasha senses that dark intentions are afoot...