Goth Kids 3: Dawn of the Posers - S17-E4
Continuity mistake: Whilst the goth kids, vampires and Edgar Allan Poe are searching the facility to find Michael, the goth kid Pete opens a door whilst searching through a corridor to see if Michael is there and then continues walking without closing the door. A few seconds later, when they are on the security camera, the door that was left open is now closed.
Answer: He appears in at least 5 other episodes, but usually just as a background character. He can be seen at Cartman's party in "Immaginationland". He was also one of the kids trying out to replace Butters in the "Professor Chaos" episode.
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