As Prim entered, his first thought was an expletive. Of course his search for solitude would not come to fruition. People avoided the training room in favor of the Dome all the time, but not the one time he wanted to be left alone. One could always argue that Thierry looking for alone time in a public place was counterproductive, but he'd likely tell that person to fuck off. As it was, he didn't have a problem with Prim on a daily basis, and there was always the chance she would go about her business and never look up and see him there. Thierry couldn't decide if that was creepy or not, though.
Naturally, the blonde was not the type to be unaware of her surroundings. He noticed that she seemed to be intent on disrobing right there in the middle of the room, which caused him to raise an eyebrow. Did girls really do that sort of thing? Should he say something? If he did, would that revoke his man card or would that make him a good guy? Thierry didn't have time to make the decision on his own, however, as soon her accusatory voice sounded from below. Busted.
"Taking a bath, what does it look like I'm doing?" he returned, raising an eyebrow at Prim's state of almost-undress. "The better question here would be why you're about to strip right in the middle of the training room, I think. Turning over a new leaf?"