["Ugh. My boss called me into his office today...and he didn't even give a reason.", 'Oh wow. I would hate that. What ended up being the issue?', "Something lame -- he wanted to see if I completed a poster he wanted. Why couldn't he have asked that over the phone?"]
Maybe he has forgotten how it feels to randomly be called into your bosses office. He's moved on up.
My boss called me into his office without giving me a reason.