He'd thought Emily had left, so the kiss shocked him and surprise kept him from responding until she was already pulling back again. But after Emily had left -- for real this time -- and the surprise wore off, that goodbye left Calvin smiling...but it didn't clarify anything for him. "Tit for tat?" he wondered to himself, smirking a little. He sighed and rolled off the bed onto the floor next to where he'd left his guitar; he pulled it into his lap and started playing, just getting lost in the music.