Finite Element Methods (FEM) is a simulation methode to solve partial differential equations (PDEs). In oder to perform FEM one needs to generate a “mesh” of the object/domain under consideration. The picture shows a meshed human body, the needed thing to perform FEM on it. Therefore one could argue that the picture shows a FEM-boy.
I (AMAB) usually go into the women’s section to buy crop tops and skirts. While being a European S, I need something like L or XL in the women’s section. So my advice would be to just browse the women’s section and add two sizes to your regular size.