noun- extremely tight jeans commonly worn by emo or skater males only. these are different from "skinny jeans" worn by "homies" in that wrong johns are even tight at the calf and ankle. from only a short distance, they appear to be "long johns" or long underwear that someone is wearing as pants, with a large belt, even though their boxers are showing. and that's just wrong. ergo, "wrong johns".
You- "I saw Jarrod wearing thermal underwear at the mall yesterday. Very strange. I guess he was there to buy pants."
Me- "Nah man. He had wrong johns on. He's quite silly".