New York, October 20 Paris Hilton recently celebrated her boyfriend Doug Reinhardt's birthday by popping out of a cake.

The socialite made the appearance in a hot pink costume and black diamond mask.

"Paris went all out for her man's birthday. No expense was spared. He had no idea about the party and was so happy," the New York Post quoted a source a saying.

Three 6 Mafia and Ya Boy performed at the party, while home videos of the couple were played on screens around the house.

The guests included Kristanna Loken and Hayden Panettiere.

The party took place in the nightclub Hilton had built inside the mansion until 3.am in the morning. (ANI)