Walter, all I know, from eyeballing those pictures, and applying a mechanical designer's grasp of weight and leverage, is that those breasts aren't of the proper density, as the women would fall on their faces in some of those poses. You saw that in Zena, too, of course. I'm betting either foam or balloons. Now, if JS could get ahold of some humongus silicone implants for bra stuffing, (Or just use water balloons.) the heft would be about right, and the women would adopt the appropriate postures.