I'm the Villainess, but I'm Too Busy Being a Fangirl, So I Don't Need Your Adoration! ~A Record of My Fight to End My Engagement With the Narcissistic Prince~

Our protagonist gets reincarnated as Amelia, the villainess from an otome game. If she follows her route, her engagement with the second prince, Elliot, will be broken off?! Just when Amelia was falling into despair, her bias appears in front of her! She decides to dedicate her life to her bias, using her engagement with Elliot as a tool in her plan. However, Elliot, who acted distant and disdainful towards Amelia in the game, is now concerned about her since she seems to be having fun while they are apart?!

(Source: MangaPlaza)