[His smile widens a little, and he shakes his head, his voice still low.] What'll I ever do with you? [He looks up to the sky for a moment, pondering that exact question before he comes to conclusion that it would be way too rude to leave her out here, and they would probably both catch a chill if they stayed overnight.
His mind then has only a few feasible options, and none of them seem particularly right. He doesn't know where she was staying. The common room may not be the safest or quietest place to leave her - and he didn't have the energy to sit and keep watch. That really only left a couple of choices...]
[Moving slowly, he turned on the grass, sliding one hand carefully below where the the bend in her knees should be - muttering something about the dress - and another behind her back. He stood slowly, carefully, making sure he didn't wake her up in the process. The last thing he needed was to be caught in the act, and have her make a big deal out of his gesture.]