Yowaki MAX Reijo Nano ni, Ratsuwan Konyakusha-sama no Kake ni Notte Shimatta

The story follows a palaeontology student who is reincarnated as Pia, the faceless villainess of an otome game called "Caroline and the Rainbow Magic Sweets." She attempts to avoid her predestined banishment by breaking off the engagement with Rufus, the Prime Minister's son, only for her fiancé to double down and offer a lucrative bet: if he does betray her before she graduates, he'll give her a hundred million gold and territory.