An NBC affiliate in Arizona is reporting that 23-year-old Tempe resident Tiffany Sutton "tricked" a 43-year-old man "with an offer of kinky sex," but things quickly turned nonconsensual:
[A]fter tying him up, police said, she pulled out a knife and cut the man on the leg. She then told him she likes to drink blood and proceeded to drink from his leg, officials said."
Link. There are fetish websites and messageboards for this stuff, but I refuse to link to them here (the only ones I'm aware of are infested with popups and malware). I've heard the term "hemophilia" used incorrectly to describe blood fetishists, but that word correctly refers instead to a blood disease.