I'm lost; what part of the dance was vulgar? The mention of genitalia was in poor taste, but I didn't see anything in the dance that made me think of anything

I'm lost; what part of the dance was vulgar? The mention of genitalia was in poor taste, but I didn't see anything in the dance that made me think of anything other than "The Wiggles" that my son used to watch. When he was 3. "Horrifically bad", sure, but "vulgar"?