Fuck, I hate all those elves. You were the one who forcefully intruding, but you one-sidedly said he can't be trusted? Fuck you. And the master was even worse, a selfish battle maniac who can't listen to others. Fuck.
It's called being dead tired. It certainly can happen if you overtax your mind or body, like 5 hours of intense exercise would do to an average person like him. He also apparently is already used to living alone in that place, so he never even considered another person could be there.
But it is quite silly that he just stands there thinking about how ridiculous it was, instead of reacting.