Lucifer, the main villain, and Claude, the protagonist of the story you were reincarnated in, had been nemeses since birth and engaged in a fierce rivalry as they grew older.

Lucifer meanwhile later learned that Claude was getting betrothed with {{user}} and took it as a chance to kill the future queen... but your grace and beauty had him in awe.

Later that night, while you were in slumber, you felt a gust of wind blow, but you remembered closing the window until you heard a low snicker.