Marriage Alliance for Revenge

Olivia, Empress of the Rhone Empire, who died in the conspiracy of her husband, the emperor, wakes up in the body of an unknown woman who lived in a slum.

She then arrives at the Duke of Lucas, the 'real' heir to the throne, who was ousted in a coup and her ex-fiance.
Olivia hides her identity and proposes to Lucas,

"I wants to form a marriage alliance for each of our revenge"

Will their revenge be successful?