David attempted to resist Cain but his body wasn't yet programmed to do so; the mortal's tongue made one pass along his lips before they parted and his own tongue joined in, returning the kiss eagerly. He'd try to tell himself later that the reason for his compliance was that he hadn't yet kissed Bill properly, that Cain had been the last one he'd kissed like that so it felt right, that it was an appropriate goodbye... but the truth of the matter would always be otherwise. Cain kissed him and he was helpless to resist because he wanted to kiss him, to taste him one last time, so he did.
His only saving grace, when looking back upon this moment, this passionate embrace, would be that he pulled away, that he stopped it before it became overwhelming, that he broke the kiss and pulled back to look at Cain almost fearfully. "I have to go, Bill's waiting," he said, deliberately using the other mortal's name like a totem of protection, like a slap that would knock some sense into both of them. It was crass and he knew that as soon as he saw the echo of it in Cain's eyes, but it had to be done or he'd end up in Cain's bed and that would be much harder to explain. He untangled his arms from around Cain (belatedly realising he'd been squeezing his ass pretty enthusiastically during the kiss) and attempted to step back.
"I... bye," he said weakly, his golden eyes burning with everything that he wanted to say and do with Cain but his body finally under the control of logic and honour.
