Selena Gomez locks lips with costar Nat Wolff on the set

Selena Gomez spent locking lips with costar Nat Wolff on the set of her upcoming movie, "Parental Guidance." The film also stars Elisabeth Shue and Dylan McDermott.

The 20-year-old singer-actress looked even younger in a short pink dress over a white blouse and bright white sneakers.

With an astonishing 12 million and counting followers on Twitter, the young Latina made Forbes' list of Social Networking Superstars. The ranking was formulated by putting together the Twitter followers and Facebook fans of the celebrities.

The top nine ahead of Selena are: Rihanna, Lady Gaga, Eminem, her boyfriend Justin Bieber, Katie Perry, Shakira, Portuguese soccer star Christiano Ronaldo, Taylor Swift, and Lil Wayne.