Sophie in Clearings (by Alex)

The idea came from a a really good friend Erik, who's working on a book right now. I really hope that it gets published despite the fact that the book will be in Norwegian(people in Norway are so lucky!)
Erik showed me a sketch of this character Sophie who's a teen fire elemental, a peasant daughter, and just figured out that she could make small flames popping out of her fingertips, and at the same time her hair floats and goes up in the air. He drew her practicing in her room before going to sleep every night and he drew that excellently. So I asked if I could contribute some artwork ideas too, and he gave be the below:-
Sophie trains in the nearby forest, the clearing has a huge boulder, and small stream running through it. She likes to sit on top of the boulder in a sort of a dip that makes the rock looks super-comfy.
So the result is somewhat weird to me too and the composition is absolutely OUT -_- I didn't know what to do with coloring Sophie because I don't know what's her favorite color, what's her eye-color, her hair color, or even how she looks like and so on.. so I decided to do this half-pencil, half-watercolor+ink+highlighter markers combination. I hope Erik likes it too ^^

P.S: Thank you so much for the compliments in my previous post(the Gun) and no, I don't own a gun :) It was a sketch from a picture.