I'm not sure what whippingpost.com is, but I can tell you (as and avid tickle magizine collector) that each of these pics were scanned from Tied & Tickled (vol. 2, num. 12) published by HOM, Inc. The layout is called "Standing Orders" and the models went by the names Vanessa & Sugar. There are 17 pictures in all, including two full-page color photos which venray1 has graciously provided for us. The story that went along with the set was about a new slave being "oriented" for their master by a more experienced slave who decides that tickle torture is the best way to precondition a new arrival.
It may be of interest to some that there is ONE smaller sized b/w photo with her strapped spread-eagle, face-up, and blindfolded on that coffee table and the other girl is tickling the sole of her left foot as she looks back at her face, smiling, to see her reaction.