Villainess Reborn: 24 Hours

The warrior Erquanna wakes in a casket and hears people making light of her death. When she shocks them by opening her eyes, she realizes she's now in the frail body of Erne de Medina, a well-known dimwit from the empire. Erne made a deal with a demon (and died in the process) that Erquanna must now fulfill. She must fall in love with one of the three strongest men in the empire—and have them fall in love with her—before her time is up and her soul is taken as payment.