Jessica Simpson Licks Tony Romo's Face

Alleged singer Jessica Simpson threw birthday boy Tony Romo a 28th b-day celebration he'll never forget: She licked cake off his face!

The PDA-packed bash took place Saturday night at Suite, a lounge in Dallas, where "she sang him 'Happy Birthday,'" reports Dallas' D Magazine.

The two really seemed to enjoy the cake, which was in the shape of a Dallas Cowboys star and had Tony Romo's No. 9 jersey number on it.

  "They were kissing with lots of messy cake!" adds a witness. "Jessica Simpson had cake all over her hands and was licking her thumbs."

Adds another D Magazine source, "It was a fun night, but it got too crazy with everyone trying to take pictures and come over. It was insane."

Hot stuff! Jessica Simpson and Tony Romo, who have been dating for about six months, says the source, "are doing great. They are really happy."

With Ashlee Simpson pregnant and engaged, how long is it gonna take for Tony Romo to pop the question - and impregnate that?