The vampire and the hunter (bakudeku)

The organization of vampire hunters, it was rarely known. Not many were aware of the creatures lurking at night. And the few who did knew best to keep their lips sealed on the matter. There weren't many rules when it came to said organization besides five.

1. Kill any vampire you see on sight. Even if it costs your own life.

2. Never show sympathy for the creatures of the night. If shown you'll be considered in leagues with them.

3. Always carry a weapon on you.

4. Never tell anyone about this organization.

5. Never befriend a vampire.

No one's ever broken these rules. Well, until izuku.