Oh yeah, that's all good. When it comes to witnessing violence, he won't even flinch. Hell, it's hard to get him to react even when he's the one being tortured. He's already been through ninja "emotional training" and he's actually a pretty zen guy - you know, when he's not on drugs.

And he'll take the slapping around rather politely up to a certain point, at which it might turn into sparring. Because that's seriously annoying, dude.