Guillotine by Delilah S. Dawson

Thrift fashionista Dez Lane doesn't want to date Patrick Ruskin; she just wants to meet his mother, the editor-in-chief of Nouveau magazine. When he invites her to his family's big Easter reunion at their lake retreat, she's certain she can put up with his arrogance and fend off his advances long enough to ask Marie Caulfield-Ruskin for an internship someone with her pedigree could never nab through the regular submission route.

When they arrive at the enormous mansion on an island in the center of a Georgia lake, Dez is floored―she's never witnessed how the 1% lives before in all their ridiculous, unnecessary luxury. But once all the family members are on the island and the ferry has departed, shit gets real. For decades, the Ruskins have made their servants sign contracts that are basically indentured servitude, and with nothing to lose, the servants have decided their only route to freedom is to get rid of the Ruskins for good…