Wow! I could never do anything like this in pen, cuz I erase so much!
I love how you did the fur, looks so real since it's going in the direction it would be growing. Very natural look'in :3

Layering over layer can correct the flow of the lines and their texture. Too simplified flow can be too unatural to look at. The good of using pen is that you can't worry about erasing! It takes some time and practice to avoid erasing- I still erase too, when i use pencil, but the more you do, the less you erase; i kinda let it for highlighing, mostly... An artist must be really confident and assured to avoid totaly the corrective erasing :)!

Ballpoint pens can be quite good medium to use! This is great example! The head is just lovely - you did great work! Even though this is "pen storm" you can find a lot of familiar shapes: I like the idea!

Yohohohohohohoho!!! !
I called it storm more because of the stroking layers it has- gives it an 'windy' feel; there bases behind it, cuz my sketching consists of catching raw forms from the pictures i look at. Yet pretty reasonable, my trainning should be more... huh... consistent and during, i say. I must agree with you, it turned out lovely foxie ! Thankies!!!