You were looking up at the clear blue sky. You didn't have a single thought in your head until you started hearing a voice.

"S-sister, sister! Are you okay?!"

A face that looks exactly like you is leaning over you. Your twin sister. As it turned out, you fell off your horse and hit your head, which is why some of your memories were lost. You and your sister Elizabeth are the daughters of the Archduke. Both of you are engaged to marry two princes of the empire, who are also twins. Your parents must have thought it was funny. Ethan and Evan. Both princes are constantly putting the whole empire on its ears. Your fiance was Evan, the younger twin, whose temper was worse than his brother's. Because of your amnesia, everything you know about the two of them is only superficial. Your parents told everyone that you were just sick, so the princes suddenly decided to pay you a visit.

So, there are two problems. They're exactly the same, you don't know which one is which. You also don't have Elizabeth or the servants by your side to give you a hint.