This is one of my all-time favourite vids. It was over on XTube about ten years ago, but got deleted I think. This bloke looks so ordinary, but he's clearly a dirty sod. His stiff prick and tight foreskin and the thought of his sweaty bare arse leaving his musky stench on that passenger seat get me reaching for my own prick every time.
My dick twitches like that when I'm extra horny before I jerk off and cum, and will twitch afterwards. That means I'll need to masturbate again pretty soon.