Little Man is a small, white, simplistic man with a long unibrow (the center of the unibrow is facing down, conveying an angry expression) 
When in his Big Man form, he becomes the size of a large building, incredibly muscular, and radiates anger and rage. He is also well drawn in this form.
Little Man is an alcoholic.
Little Man seems to control the instrumental as well, so what can I say? He's like a professional memer.
He is a pro Clash of Clans gamer and fluent at Glass Breaking language.