Farrah Abraham Twerks on Master P on 'TMZ After Dark' Tour

Master P might be in control in the studio ... but, Farrah Abraham took charge while with him on the TMZ Tour Bus -- throwing it back in his face Saturday night!

Our "TMZ After Dark" tour is so popular we've decided to add a second bus on Saturday nights to give more fans a chance to experience a wild evening out in Hollywood ... and, we got the two stars to each host one of the rides!

Master P's bus left at 7:30 PM while Farrah's left at 8 PM ... but, the two stars got on the same bus for a minute -- during which Farrah out on a show using the pole up front.

Check it out ... Farrah shakes her backside to the music and -- while she doesn't seem to touch Master P -- she's certainly giving the star an eyeful.

Like we said, after this Master P's bus -- with DJ Teo at the turntables -- took off ... stopping by "Star Wars"-themed bar Scum & Villainy before hitting Bar Next Door and then Saddle Ranch, where riders had the chance to ride a mechanical bull.

Farrah's left at 8 PM ... and, while DJ ELLE played tunes, the bus made its way to the Burgundy Room, TomTom and Roosterfish. Riders stop for drinks at each place ... and, one lucky lady even did a body shot off Farrah's chest!

We also got the scoop on the Farrah and Master P's future plans ... with Abraham letting us know she's heading off to law school -- while Master P's challenging the great Shaquille O'Neal to a DJ/sports contest!

Master P summed it up best ... saying whatever happens on our bus, stays on our bus.