Also, the index finger of a hand does not bend that far behind the middle finger at that particular angle when the fingers are crossed. Learn human anatomy. It will only help you later on. Cross your own fingers and observe how they look. The kinematics of your knuckles are such that there is esistance past a certain point in the joint. Because of the strength of the muscles and tendons in your hand you would have to actually break your forefinger to position it the way that you are depicting.
One finger can not physically go through the side of the other one, either.
Don't forget the eraser!