Sir, Who Are You Today?

His fiancée, His Excellency the Duke, has multiple personalities! ? Harem romantic comedy with one opponent begins! Alma decided to proceed with the marriage with the duke's family. There is a reason for her fiancée, but when I talk to him, he is a surprisingly good person! However, the moment after receiving the proposal, his personality became a "different person". What will happen to this matchmaking!?