I wanted to use the body of Assassin_05 for something else, so I pulled off her clothing and found that there is no visible body between her hips and her knees.  I know I can remove parts of a body by masking things out, but there are not any masks in her maps.  This has happened with a couple other characters as well.  One example is when I turned a dwarf into a giant and the boots cut off parts of the leg.   
So how is this body masked out without a mask, and is there any way to stop it from doing so?
Thanks!