[Wolfram's first reaction is to be left speechless, which is soon followed by anger. "What the hell do you know, Josak!?" or "That doesn't concerns you at all!"... it takes a lot of effort to hold those words back.
If he says those words not only he'd behave like the emotional brat he's always been, he'd probably upset Josak too. So instead, he forces himself to calm down.] That... dare is far from easy. I might not be able to go through it.