Pretty cool. I like his story (though I wonder why he didn't take the party's offer - were you tired of the character?)

The use of colours in the picture is good. It feels, well, fox-like

One problem. You say he's a humanoid? In this picture, though, he looks just like a regular fox dressing up and dualwielding.
I'm not even sure how a fox can even hold swords. He needs to look a lot more human before that's plausible.

Other than that, good job. The Zorro associations only make it cooler.