That guy has a lot of posters of stolen work and I don't know how eBay works, but they should have taken down his account since long time ago.
Is really upsetting, you may want to look up for the other deviants that have been affected by this person and see if you can take legal action, since he's obviously earning some money out of your work.
I would totally report their ass if I had an ebay account, seems stupid that you have to have an account to something as basic as report them for theft.
He's store is all about stolen prints from DA!!
That should get some action outta eBay.
Is really upsetting, you may want to look up for the other deviants that have been affected by this person and see if you can take legal action, since he's obviously earning some money out of your work.