Toxic?

[ that gets him worried. lop immediately looks at his hand, then down at himself, nervously shifting to squint at the spots where his clothes have burnt through a little. ]

I -- I'm not sure. [ an anxious noise from the back of his throat as he checks his arm for any burns. ] Can I ask what exactly happened to cause those flames? It doesn't look like there's anything to cause it, and it vanished so quickly ...