Richie

Background
Sam and Dean bump into Richie in Elizabethville, Ohio, while investigating strange happenings seemingly caused by demon activity. Dean recognises Richie - their conversation suggests that Dean met Richie on a hunt, saving Richie from a succubus in Ganovski(?). The fact that Sam doesn't know Richie suggests that this may have occurred during the years Sam was at Stanford. It seems that following this experience, Richie has decided to become a hunter, but Dean doubts his capabilities and urges him to step down.

Richie is killed by a demon in 3.04 when she lures him into her basement with the promise of sex, knowing he is a hunter.