Sanguini is a vampire who attended a Slug Club Christmas party during Harry Potter's sixth year at Hogwarts. He was the guest of Eldred Worple. The tall, emaciated man had dark shadows under his eyes and looked bored with the party until a nearby group of girls attracted his attention. Worple tried to distract him from the girls by shoving a pasty into his mouth.
Name etymology
The name Sanguini most likely originates from the French "sang", meaning blood and hence vampirism. It could also come from exsanguination, which means to bleed out.