I assume your talking about "grinding" or "freaking" right? Thats the only type of dancing that goes on in my school. Girls usually have a specifice rhythm they do with their ass, so all you do is put your croch against her ass and follow her rythm. Its not hard usually they just go up and down, or some curcular motion. After 30 seconds youll know her rythm, and it will be easy.
I also suggest googling this search...I once found years a go this site, where it shows you step by step instructions and videos for reference.
Sincerely
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