"I'm suddenly breaking off our engagement!" I was told. It's a case of mistaken identity.

At a peaceful academy graduation ceremony, a handsome prince suddenly appears! "You're the marquis's daughter, right? I've decided to break off our engagement with you!" Huh?! That can't be true!! Even though this is like the opening of a classic romance drama... I've been mistaken for someone else! A small love-like story that begins with "What do I do about this situation..."