Gwen Stefani is currently delighting the crowds with her Just A Girl residency at Las Vegas' Planet Hollywood, and fans who showed up on Wednesday night (Feb. 19) got a special treat. Stefani's boyfriend, Blake Shelton, made an unexpected appearance to perform the couple's latest duet, "Nobody But You."

Prior to the duet, Stefani, dressed in her residency's cowgirl outfit (boots and fringe) addressed the crowd that evening during a contemplative moment, thinking back on her overall career. She note, "I was looking on iTunes this morning and I'm number one on the country chart ... I just thought that was like, kind of incredible."

That seemed to be the perfect time for Shelton to make his appearance—which he did, to the delight of the crowd. The two performed their duet, and Stefani, overcome with delight, jumped up and wrapped her legs around her boyfriend's waist in glee at the end of the song.

This was a nice coda to the couple's Valentine's Day, which the lovebirds spent apart due to their conflicting schedules, but Shelton still rose to the occasion by sending a huge and beautiful floral bouquet to delight his best girl.

Shelton and Stefani have been dating since 2015 and battled against one another on The Voice. Stefani is currently taking a season off from the hit competition show, while Nick Jonas takes her place as a coach when the season kicks off later this month. 

Shelton is currently on his 2020 Friends and Heroes Tour with the Bellamy Brothers, John Anderson, Trace Adkins and Lauren Alaina. Stefani is holding down her residency, though she canceled her Feb. 14 show due to illness.

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