[The sting of a remark cutting far too close to the bone gives him pause for a split second too long. He blinks away a blank, inward-searching look in his eyes, casting words of his own like stones in the heat of the moment in a bid to cut short this frustrating subject.]

Neither I nor my affairs are any concern of yours… but should you persist, God help you, I will become one. No matter what tortures your friend is prepared to inflict.

[Even as he says it, though, he knows it'd be too impetuous of him to follow through in the manner he's suggesting. But physical threats aren't the only means of shaking off someone bothersome; they're only the most familiar to him.]