Jack Satchel Skin of Evil

Jack Replaces Tasha Yar on the away team after she's incapacitated by Armus. He was talking with Lore, Selar and Geordi when he was sucked into Armus and subjected to painful torture until Armus got pissed off enough that he just spit Jack out. By the end of the episode he still had a few signs of the ooze on him.

Note: I said Tasha is Incapacitated because she's later revived with help from Reginald Ranor, Kitana Ranor, Selar and Alyssa Ogawa.