I really love the idea because I love Pokemon. The sticker is cute, and is definitely something I would use!

I think the head shape and eye position is slightly odd, giving him an "alien" feel. This could be a stylistic choice, but it puts me off a little bit.

Also, Charmander has three toes, but again this could be a stylistic choice.

I really love the way the fire looks and how it overlaps with his tail. I also think it's great that you did the shading so that you can tell light is coming from the fire. Nice observation!

Lastly: I think the pictures you used are great! It shows a flat detail of what the image looks like, a neat looking perspective shot, and an image showing size.