Dokushin Shugi no Reijou wa, Koushaku-sama no Dekiai kara Nogaretai

I want to break off the engagement, but for some reason the Duke won't let me go! Countess Erentina had vowed to be celibate in order to hide her "witch" status. Just when she thinks she has finally managed to break off her engagement, the Duke of Arden asks her to marry him! She doesn't want to get married while keeping her true identity a secret, so she decides to have the engagement broken off! I decided to do everything I could to get him to break off the engagement, but the Duke embraced me and... But the Duke embraces me... "From now on, we'll always be together," isn't he getting sweeter and sweeter? Source: MU