My girlfriend went ahead and photoshopped the background from white to black and all so added a reflection but she hasn't touched the figure itself in any way. We would like to know if it's ethical to use these photos in an eBay auction. Please state any reasoning as to why or why not to use these photos. Thank You!

 

I don't see why not, the figure itself has not been altered in any way

 

The only problem is see with this is the reflection. You can tell that part is PS'd.
If you didn't say anything about the background, I would not have noticed it.
Once I knew it was PS'd, I can see the signs of a background change (small white fringe).
If you were just using these pics for a thread here, it would be cool.
But your wanting to use it for a sale on Ebay.
I can see the problem of people not trusting whats "real" in your pic.
Even if you state what PS work has been done to the photos.
Just my  

 

I'd assume I was getting two Optimuses.

Anyway, for ebay, if you ever ran into trouble with a buyer that said what you sent him wasn't what was pictured, they might ask you if the image had been altered. And that is probably more trouble than it is worth.