Gwen Stefani, Blake Shelton Flirt, Goof Off Together on The Voice Set

Love at first bite? Gwen Stefani and Blake Shelton got goofy with their costars on The Voice on Monday, Dec. 7, posing for an up close and very personal selfie during a commercial break.

The lovebirds, along with fellow coaches Pharrell Williams and Adam Levine, convened around Shelton's chair and snapped a pic that Stefani, 46, later shared via Twitter. In it, the country crooner, 39, pretends to bite his girlfriend's shoulder as Williams and Levine stand on either side of them.

An onlooker tells Us Weekly that the "Used to Love You" songstress and her beau spent several commercial breaks together on Monday, and were seen whispering and laughing throughout the night.

As previously reported, Shelton also performed during the show. He sang his new single, "Gonna," after which Stefani gave him a standing ovation.

Interestingly, the tune contains a sly (and perhaps inadvertent) reference to the No Doubt frontwoman's musical past. In one verse, Shelton sings, "Gonna put a rock steady on your hand"; Rock Steady is the name of No Doubt's 2001 album.

Stefani's rep confirmed exclusively to Us in November that the two had recently started dating. Both split from their spouses, Gavin Rossdale and Miranda Lambert, this past summer.

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