So im writing a story where a sidecharacter who is a vampire attends Hogwarts and am a bit confused on the topic of vampires. In HBP we see Sanguini in the Slug Club who seems harmless? I mean they would never have let him near children if he was a mindless bloodsucker right? Also generally we see vampires interacting normally with the magical world. So it seems like they can somewhat control themselves, unlike say werewolves during full moon. At the same time they are also really dark and dangerous? How likely would it be for a vampire to attend Hogwarts under Dumbledore with high supervision? Maybe having a special diet would work? What about laws? Are there any that prohibit them from attending?