what if, he did that on purpose to get your attention? Like bothering you is his way of expressing his feelings for you, but he himself is also not aware of his feelings and is always in denial about it. He's purposely asking questions so he can communicate with you, and when he finds out you're in the same group, he's kinda excited... maybe? he's still in denial state. The two of you in the library.... what's he going to do besides making project?