Edit: (omg this was fun, I'm going to have to make more things! :D )
I went for armor! I'm picturing it as a light but durable thing made from black or very dark brown embossed leather, reinforced and/or decorated with emboss or steel. Since it looks quite different depending on how you combine embossing and steel I made several versions to give a feel for what it might look like.
I left a gap by the shoulder for where her wings would be, and the face guard also has room for the horn. The thing is held together with leather straps and metal buckles, so I'd suggest making it custom... otherwise you'd have a heck of a time getting it on and off!
Since Ghost has a wolf companion I chose to add paw prints to the decor, but that's of course optional; I have the .psd saved so if you want anything changed like color or symbols etc it's an easy fix!
Leather with steel decorations
Steel reinforcement, embossing and steel paw prints.
Leather embossing with steel paws
Fully reinfoced with complete decor in steel
Only leather, all decor is embossed