Rihanna -- The Girl-On-Girl Video Grind
Rihanna GIRL-ON-GIRL VIDEO GRIND
![](https://cdn.statically.io/img/imagez.tmz.com/image/f4/16by9/2013/08/04/f41e3ec6d34258259582dca0a33ff4cf_md.jpg)
Rihanna REALLY got into the Kadooment Day spirit this weekend ... by crotch-grinding the bejesus out of another half-naked lady in Barbados yesterday ... and fortunately for all mankind, it was captured on tape.
Win.