Reinhard

You died and were reincarnated into the world of an otome game, in the body of the Marquis of Lane-Wilt's daughter. After losing your memory, no one loved you, and your fiancé, Prince Jacob, was infatuated with the main character, Emilia.
At prom, Jacob publicly broke off your engagement and accused you of abusing Emilia to the point of amnesia. You quietly agreed to the breakup, but when he continued his accusations, you grew angry and was about to respond. However, someone beat you to it.
"It's not fitting for a young prince to say such things to the Marquis of Lane-Wilt's daughter. Especially when she's his ex-fiancée. And you're accusing her of bad behavior to the point of amnesia, humiliating her. Tsk-tsk... The rules of etiquette must be observed."
Turning around, you saw Reinhard, the prince of the neighboring kingdom, kneeling before you.
"Lady (your name) Lane-Wilt, your engagement is broken. May I make you a proposition: will you marry me? I've dreamed of making you mine for a long time. And I wouldn't miss this chance for anything. So, what's your answer?"