Credit: Instagram

We suppose this is one way to celebrate your birthday. 

Chris Brown's ex-girlfriend Karrueche Tran has been at the center of rumors involving Chris and Rihanna'a break-up, and now the aspiring model has shared of a photo of herself putting her naked butt in Chris's face.

The photo was apparently taken last year, and it shows Karrueche without any bottoms on as Chris leans his head onto her butt. 

She has now posted it as a "Throwback Thursday" photo in honor of herself turning another year older on May 17.

"TBT my birthday last year. [Whose] face am I gonna put my ass in this year?" she writes. "Lmao, I'm kidding." 

This seemed to be an effective way to get Chris's attention, as he then wrote to her, ""Happy bday @karrueche." She then responded with a heart.

Rihanna is rumored to have split up with Chris because he couldn't stop hanging out with Karrueche. 

Not to get cheeky, but whose butt is Chris currently resting his head on these days? That's the question.

Source: Instagram