Well, I haven't gotten to this point in the series yet, but in the book, there's a point where he's being held captive by Thenardier and his gang and they threaten to torture information out of him so they can kidnap Cosette. So he picks up a burning fire poker and BURNS HIMSELF to prove that won't crack under pain and generally just freak everyone out. Hardcore, right?
"Jean, oh my god, stop doing that! It's scaring all the other guests! I'm not inviting you to my parties anymore. Not cool."