I'm The Villainess, So I'm Taming the Final Boss Vol 2

I'm the Villainess, So I'm Taming the Final Boss by Sarasa Nagase. A Fantasy manga rated Teen, published in English by Yen Press.

The moment Aileen's fiancé, the crown prince, breaks off their engagement, she remembers her past life and realizes she's the villainess of an otome game headed for a grim ending. Her plan to survive? Win over the game's final boss, the demon king Claude, before the story can destroy them both.