I *think* he means a layer is a photocopy on 
paper. I guess the photocopy is easier than 
getting someone to paint you a layer. I've seen 
this done a lot when the cel has some weird 
lines in it from missing stuff (like tables or a 
person that's supposed to be there).  I've also 
seen a few cels that have painted heads and 
photocopy bodies but the sellers have always 
been careful to point this out.  

Have you tried to talk to the seller about it?  
The first thing I do when I've been royally 
screwed by a seller is check the item 
description to make sure I didn't misread, then 
(if I didn't) I unleash the fury.  ^_^  Okay, so 
I start out with a polite inquiry, THEN I 
unleash the fury.