Refraction

A more decent picture of the White Spirit, for reference.

The white spirit does not have a defined form, nor is it a creature that can be invoked. Instead, it has to be created, and its shape and characteristics will vary according to the mental state and memory of the prism and the fox used to create it. So, there could be tons of different versions of it- this is just Alan and Chris' one.

Since Alan was way more conscious about the existence of the white spirit, he created most part of it. He is a fox, and he was "raised" as a bearer by a fox and a wolf- that's why the White Spirit looks like these animals. Alan sees spirits as something incredibly beautiful and haunting, yet he feels scared of them, which gave this creature a look of perpetual fear. The colors are faint, because of his lack of knowledge.
The broken wings are what Chris added to the "design"- the bearers he knows are an owl and a wolf, so these are the colors he used the most. The creature only has bird-like wings instead of other features, because Pepper never showed Chris anything but her wings. The bad experiences he had with spirits in the past (being attacked by officers and his father's death) made these features look broken and bloody- he associates spirits with violence and pain.

Ewwww that was a long paragraph.
Anyways
'njoy.