"Pia Sands" is better known to the mainstream world as Michelle Bauer, star of HOLLYWOOD CHAINSAW HOOKERS. I couldn't say whether she's ticklish in real life but clearly her reactions in this video were more a tribute to her acting talent, since the guy who's supposed to be tickling her barely touches her, just flopping his fingers around like a handful of dead fish. HOWEVER:
The video is worth seeing for the "revenge" scene later on when "Pia" and the guy tickle his blonde girl friend who's tied to a bed. "Pia" is tickling the helpless girl for all she's worth (and really getting into it) and at one point turns to the other "actor" and says "Come on, REALLY tickle her!" He does for a few seconds and you can see the difference in the blond girl's response.
A classic!