He's the Big Boss, the Evil Overlord, or some other higher-up either good or bad. When he receives people in his office, instead of looking at them directly, he talks with his back to them while looking out the window, probably with his arms folded behind him. Usually intended to convey that the character is so badass he can't be bothered to look at his audience, this is sometimes used to indicate an internal conflict of some sort (depending on his facial expression). Also has the bonus of keeping his identity a secret, up until the Chair Reveal. This may be part of The Faceless.