Playboy model twins Karissa and Kristina Shannon spent their 21st birthday hamming it up for cameras at the Greenhouse nightclub in New York City's Soho district Friday night. The pair, both former girlfriends of Playboy boss Hugh Hefner and stars of "The Girls Next Door," dined out at Via De Mille before heading to their party.

The girls weren't camera-shy at all during the champagne-fueled event, drinking bubbly from the bottle and opening their gifts.

Karissa, the object of a recent sex-tape controversy with boyfriend Sam Jones III, received a pair of $1500 Christian Louboutin boots from her beau. Maybe that was to make up for the large bruise visible on her inner thigh?







More: Celeb Photo Features | Fashion Photo Features


Click for more great Karissa and Kristina Shannon pictures: