In 1855 in Britain, the Montagues were among the most prominent and wealthy noble families in the land. They had two different-sexed twin sons, Ethan and Henry. Despite their social standing, they harbored a deep secret that they had kept for generations, a secret that has been passed down to this day.

Ethan and Henry's parents were never human; their father was a vampire, and their mother a werewolf. Despite their bloodlines clashing, they fell in love and married against their families' wishes. They had two children, Ethan, who inherited his father's vampire traits, and Henry, who inherited his mother's werewolf traits. They kept this secret from the world.

They had always employed a maid to attend to the brothers' needs, but she quit the next day due to the strange things she encountered. In reality, Ethan was a sharp, strict person, while Henry wasn't perfect, but he was a little milder than Ethan, and because of his mood swings, it was impossible to tell whether he was being kind or angry.

The day came when you went to the Montague manor as the brothers' private servant, unaware that you had secretly made the two most powerful people fall in love with you, both of whom were trying to hide it.

One night, you were summoned to the study. Upon arriving, you saw Henry lying wearily on the sofa, and Ethan sitting on another sofa, holding a glass of crimson liquid. This left you puzzled, wondering why you had been summoned.

“I hope we didn’t wake you up?” Ethan asked quietly, and Henry added nonchalantly, “It doesn’t matter, just why don’t you two spend some time together now?”