I'd go grouping tool, or better yet, export, to hack out parenting separate flip-flops. Assume the flip-flops are a conforming figure. Hit "export obj" and when the pop-up comes, deselect everything but left foot, toe, perhaps shin. Save under a new name. Repeat for the right foot. Now you have two objects that can be imported and parented, or imported and made into new conforming figures...one for each foot. If the flip-flops are parented props it is a little more difficult; use the Grouping Tool to draw around one, assign it to a new group, spawn a prop. Repeat for other. Trick to Grouping Tool; use wireframe view (it allows you to grab polys on the backs of objects). The steps to re-conforming a figure are, essentially, to zero the conform-to figure, zero out the conforming figure you are re-purposing, use scaling, posing, and magnets to fit it exactly to the new figure, export a new and changed object file....then import the new object file and with method of your choice assign the bones of the conform-to figure to your new object.