This is a very good sketch, sephi, your proportions are very good and I like his pose. As I said, I'll be very happy to help you with some stuff as soon as I finish the project I'm working on now. I have a great reference pic of a squirrel we can use to practice your realism on.
This totally needs a background and i like how it looks like its was drawn in crayon. if you want an idea ad the brown and silvery color to the fur. and make the ground have dead leaves on it. and an eggcorn top.
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