I highly recommend "Your Highness Vampire, Please Have Respect". The female protagonist of this fantasy and magical fantasy novel, Fanjo Man, was a vampire duke, but she was sent to a school for demons and vampires. The rulers of the demon world and the vampire world fell in love with her at the same time, but the heroine loved both of them. Later, the female protagonist mysteriously disappeared, and the demon ruler and the vampire ruler joined forces to find her. After finding her, they found that she was the person they were looking for. There were demons, vampires, and princes in this novel. It was exciting and romantic enough! I hope you like my recommendation. Muah ~