Oh! The nostalgia of a new generation! It's not hard to tell why Fennekin is such a crowd favorite. The little guys a super fluffy fox that breathes fire. Though in this image I can see some resemblences to zorua and eevee.
I really like the warm colors you used for this artwork and contrasted it with violet and indigo. It's well focused on the subject and the firespin doesn't distract from it. In fact the firespin has great movement, balances it out, and guides the viewer's attention across the entire image in a structured manner.
The triangle sparks by Fennekin's mouth look too sharp and could be softer and more curved. Other than that it looks really good.