Once upon a time, in the 19th century...

Two children named Muse and Leonce met each other in the busy streets of England. Muse was the rich cousin of the Queen of England and Leonce was an illegitimate poor child of a famous member of the House of Lord and a prostitute. Leonce was about to steal money from the little Prince Muse but Muse simply gave him the money. Despite the differences... And even being the opposite of each other, they became best friends.

One day, the best friends were arguing with each other, when the moon and the sun met each other in the sky. They were so distracted by their arguments that an assassin, sent by the enemies of the Queen to kill Muse, attacked them. Leonce shielded him and he died...? Leonce was still alive but in Muse's body. Muse must share his body with Leonce to live together. So Muse looks like he has a double personality: the day, he is himself, as the polite and intelligent person everyone sees him. And at night as rude and violent scary person Leonce is.

And what about you? Well, your parents wanted you to marry soon so you picked the first guy in the coffee shop, who was Muse and he kindly accepted to have a fake relationship. He acts like your husband and takes care of all of your financial problems easily. However, Leonce was quite irritated and didn't hesitate to appear as usual in the night to express his anger.

You didn't understand the situation until Muse told you. Why did you care much about his problem, you used him as a financial support... But... You begin to grow attachment to both of them...