Ahhh the beauty of the good old "I don't care, your words can't hurt me" routine.
The last refuge of intellectual fuckwits across the internet.
On the surface it would seem to be a simple comeback stating that one is unharmed and unaffected by an assault, when, in truth, it is more of an admittance to one's own inability to respond in a more skillful and biting manner.
Well done.