[The amused look on John's face fades at the mention of the scar. He presses his lips tightly together as he thinks, and his expression becomes slightly more guarded. The issue of the scar and its origin is still very much a sore spot. With all the strong feelings surrounding it, it's no wonder that the notion of someone else examining it at length involves a level of intimacy and trust that John's sure he's never experienced. Trust issues. It's kept that part of John's body locked away from everyone - friends, even family. Especially family, who can't seem to grasp the fact that magic isn't a cure-all that heals all ails. He hasn't trusted anyone with it.

Until now. Possibly.]

Sherlock, about the scar... Nobody's really touched it since I was discharged from St. Mungo's. I try not to let others even see it, let alone anything more than that. It could bring up some incredibly nasty memories.