He doesn't understand at all. But the thought flashes across his mind that he can hardly judge - he's wearing a ring that he could take off, only he can't, doesn't want to, won't. He can't cast stones about ownership or relationships when he doesn't even understand his own.

Besides, he is not going to spoil this. It feels too good to stop. So he kisses her back, fingers stroking her sides under he pulls back and says, throatily;

'C'mon, upstairs. Lets do it properly.'