I bought this as a gift for one of my good friends for Christmas (a 19 year old female). She was big into the raver scene for a while and always wanted a plush backpack, but never got one. She doesn't rave anymore now, but I know she would feel thought of if I got her this, and it was a HUGE SUCCESS.
It shouldn't be called a backpack, more like a pillow with straps and a pocket. The pocket is on the yellow-part of the shell, the part which would be against your back if you were wearing it as a bag. The pocket is 6 inches by 6 inches if I had to guess, and could probably fir something 2-4 inches in depth, so about the size of a wii.
The shell is perfect, IT'S SO FLUFFY! I am now looking for a red one to buy myself.