Kate Middleton showed her bloodthirsty side as she drank from blood bags during a Halloween night out. The royal girlfriend showed up to Mahiki for its ­Halloween bash and was obviously in the mood to party.

Hitting the dancefloor ­immediately, Kate showed off some moves with her sister Pippa and model Lily Donaldson­. She then joined a table of friends to knock back the rum-based blood-like cocktails from replica blood donation bags.

“She was getting stuck into the blood bags,” a clubber told us. “They were all making vampire­ jokes and it was all over their faces.”

The fashion worker was assigned­ her own royal protection for the night – in the form of a posse of boyfriend Prince William’s pals.

Guy Pelly, who works at the venue, Holly Branson and other friends of the Prince kept an eye out for Kate all night, making sure she was looked after and that people didn’t tread on her witch ­outfit. Kate turned up to the cocktail bar with a full costume­, but only unveiled it inside, after getting friends to carry it in for her.

“It looked like she didn’t want to be photographed in it,” an onlooker said. There was no sign of William, but given the Royal Family’s history­ with dressing up, we think that perhaps was a good thing. (via TheLondonPaper)