The 9th Grader with Purple Shirt is an unnamed character who appeared in Season 5 episode "Scott Tenorman Must Die", where he and another unnamed 9th Grader are seen as friends of Scott Tenorman.
Background
He was spotted earlier in the episode talking to Scott Tenorman and another 9th Grader. Scott was telling them that he sold his pubes to Cartman. Scott later learned that Cartman wanted revenge on him, so he decided to make a pube chili to humiliate Cartman. Later the 9th Grader with Purple Shirt and the other 9th Grader bring the pubes to Scott, according to them were pubes of almost every child in town. They later appear at the end of the episode seeing Cartman revealing to Scott that his parents were killed by Farmer Denkins.
Appearance
He has long brown hair and wears a blue hat similar to Stan Marsh's, a long-sleeved purple shirt, gray pants, and blue white shoes.