The Game -- BLOODY GIRL FIGHT ... After Nightclub Twerk-Off

A night of innocent booty shaking turned VIOLENT at The Game's birthday party in L.A. last night -- when several women straight up BRAWLED in the street ... and TMZ has the footage.

It all went down outside in front of a Hollywood nightclub -- where one of the women put on a twerk show for the rapper earlier in the night while he was inside of his car.

A short time later, the woman gets into a fight with another clubber and it sounds like they were arguing over a man. One thing led to another ... and they were full on fighting in the street.

There was hairpulling ... shoes were used as weapons ... a couple of boobs fell out ... and one of the fighters was left covered in blood.

Cops eventually arrived and at least one of the women was handcuffed.

Just another night out in Hollywood.