VIDEO: Justin Bieber Spoofs Own Perfume Commercial 'Someday' with Jimmy Fallon

Someday, Justin Bieber might not be the pop sensation he is today. But at least he has a sense of humor about it.

Bieber appeared on "Late Night with Jimmy Fallon" in a sketch spoofing his perfume commercial. The original commercial was a hit with fans, as it featured Bieber whispering things like "Someday...we'll be together" to the camera.

In the sketch with Fallon, things starts out the same way...but then Bieber switches gears and whispers, "Someday...I'll get old and fat." Enter Fallon, wearing a Bieber-esque wig, who seconds that thought: "Someday...you'll look like me," he whispers. Jimmy/Future Bieber then gives the young Bieber some advice about keeping his metabolism up and hiring a trainer.

The two finish up with some great non-sequitur "somedays," including "Someday...video games will be an Olympic sport," and, "Someday...we'll all have robot arms and eat tacos made out of light."

The whole thing is pretty darned funny, and a solid performance from the Biebz. Check out the video below: