The Vampire of Hogwarts

The vampire clan has long existed in the magical world, hidden among humans and wizards. The arrival of a transmigrator shatters their peaceful isolation.

Edward Campbell, seeking to atone for his family's sins, enters the world of wizards and gets into the long-coveted Hogwarts as a spy. His mission is to sow discord between the Ministry of Magic and Voldemort, ensuring that both sides are locked in a bitter struggle so the vampire clan can seize its share of the magical world's spoils.

Time is short and the mission is urgent, but Edward, who knows the story, isn't worried. After all, how is going undercover at Hogwarts any different from taking a vacation? Harry, Hermione, and Ron, the familiar trio; the kind and wise Dumbledore; and Fleur Delacour, the senior from Beauxbatons... Sorry, Edward just can't wait!

(I'm trying to imitate the original's style as much as possible. The male lead starts Hogwarts in his fourth year, Fleur Delacour is the heroine, and the male lead sides with the vampires. He's kindhearted but cool-headed and decisive when it comes to killing, and he is sorted into Ravenclaw.)