I think it's safe to say that she gets it that he went and brought it in the room for her. By now she's fairly acquainted with the room itself and there's no way she'd not notice a thick manga volume with booby girl laying out in the open under the blackboard or where was it. So... Yeah... Can't say the same for the friends, though. Also to all this talk about their relationships developing: well, if you'd check the original dojins, the first one, actually, it end with him basically confessing to her and them agreeing to start dating each other. Yeah. I wonder where the story is headed, indeed I do~