You just sit down.
“And if I stay here against your advice, are you going to try and stop me? I don’t exactly have all the time in the world, but there’s not much I can do if you’re not giving me even one device. So, I might as well just sit here.”
“Maybe I hit you harder than I thought,” the grebling grumbles. “You can’t dodge every swing I make at you, and even if you could, dodges like that won’t exactly help you.”
“But even if you do hit me again, I’m not leaving,” you reply. “So it’s really a question of how far you’re willing to go. I don’t think it’s far enough to get rid of me.”
“Is that a challenge?” he asks.
“It’s an assessment,” you clarify. “You’ve told yourself you want to be left alone. I don’t think you really do, and I must be the only company you’ve had in however long it is. So part of you is going to always hold back, and you’ve noticed. That’s why you’re trying harder to dissuade me with your words, because that’s the only chance you have now. You know you can’t push me away with force.”
Silence. Probably thinking of how to respond. You think your best chance of securing your advantage is to give them a prediction of their next move just before they do it.
“You’re about to ask me for something impossible to get in exchange for the artifacts, just to get rid of me, are you not?” Offer him an alternative, valuable gift instead
Say: “Your next line is: Just kick rocks already. Right?” You have such a strong read on him, you both say it at the same time. Time the last “right?” After he gasps in surprise.
Since you said “how far you can take it” he’s probably going to beat you up a little more after what you said, so you stand up again, in a defensive stance
Offer him company and therapy after this is done