Bhad Bhabie: 'Mama Don't Worry' ... I'm Just Grinding on Pia Mia!

Bhad Bhabie just killed her sold-out show and ended the night by backing her thang up on Pia Mia (remember, B.B. is only 15).

The rapper performed on Thursday night at the legendary Roxy in Los Angeles and, love her or hate her, she's getting butts in the seat, just not hers.

Bhabie was all over Pia during one of her songs and while the crowd ate it up, the singer (who's seven years older than Bhabie) seemed a little uncomfortable with all the booty shaking.

That all ended though when Pia jumped off the chair and started throwing bills into the audience. The whole thing seemed really fun, just not sure if it's what every 15-year-old's mom would want them to be doing on a school night.

But Bhabie isn't just any teenager — she has nearly 14 million followers, a hit with Ty Dolla Sign and no matter how hard we try to shake her, she's not going anywhere.