We all know Rihanna is one tough chick.  This video is solid proof of the fact.  Rihanna was playing a show in the UK last week when she decided to walk around the front of the stage to meet her fans.  One particular fan wouldn't let go, and you can see for your self what happened!  Rihanna took to her twitter account to explain she wasn't at all sorry.

"Purpose! That b— won't let me go,"