Brian McKnight Drops New 'Anal' Song -- Way Dirtier Than 'P**sy' Tune

We didn't think it was possible, but Brian McKnight's new track makes his "p**sy" song sound like a "Barney" jingle -- and of course TMZ has obtained a clip of the new jam.

Brian wrote the track for YouPorn.com as a thank you ... after the porn mega-site sent sales of Brian's "p**sy" song through the roof. You know the lyrics by now. Everybody, "Let me show you how your p**sy works. Since you didn't bring it to me first."

So the folks at YouPorn suggested Brian could show his gratitude by writing them an anthem ... and boy did he deliver.

We won't post all the lyrics -- just listen for yourself .... but here's a taste ... "You wanna see some f**king anal, I can get you close enough to smell."