What is two chicks one cup ?

After seeing several 'reaction to 2 girls 1 cup' videos on youtube curiosity got the better of me and I watched it the video... its basically a 2 minute video of 2 girls, one sh*ts in a cup, they both lick it, puke, and lick that too... its totally dumb, just a gross out video, the reactions are much more amusing than the video!!