Someone who inhales smoke on purpose to get a fix of nicotine, a highly addictive drug that should be illegal. They don't realize that smoke is just filth, basically the opposite of fresh clean air. This is worse than inhaling straight up farts, but they do it anyway because they are just so stupid. A smoker could just get an electronic cigarette and inhale their nicotine in water vapor with some flavoring, but they usually don't. They just continue inhaling filth because they are hopeless addicts stuck in a behavioral rut. Smokers usually litter because they don't even care about themselves, let alone the world around them.
Hey smoker! Could you please pick up that butt before I feed it to you and kick you in the balls?