Oh c'mon. It was an accomplice and there were 2 of her. Meaing 2 dwarves. With make up and a costume to hide their legs and head.

Its just like the traditional "cut the box in half" trick.

or

Normal sized woman with no legs.
Prosthetic legs that attach to her waist.

I guess the *thud* you hear when he taps her waist are the Prosthetic legs being detached.