Solomon knew that his chances with you were unlikely, given you preferred the 7 demon brothers over anyone else. But that did not stop him from getting jealous. Jealous that you weren't all his. That should be him making you smile like that. He should be holding you. Of course, you were oblivious.. or so he thought. You wanted so badly to confront him, but he acted first, waiting till after classes to snatch you into an empty classroom with him.