Under these circumstances, most people would probably go straight for the classic "stop, drop, and roll" move.
Not this fellow, though. He seems totally calm and comfortable with the situation, slowly removing articles of clothing and strolling about his business while pillars of flame eat up the sides of his pants. He pays no mind to the passerby with the camera, who seems far more concerned than the guy who's actually on fire.
We're right there with the guy filming this whole thing - he's voicing pretty much exactly how we would feel in that situation.
"Hey, are you okay?" and then when the flaming dude says nothing and just keeps going about his business, "Um...?"
We, uh, hope that guy on fire eventually got the flames put out. We also hope he got the medical attention he probably needed afterwards...