Sirius laughed when James teased him. "I know, that's why it's only ever something I think about and not something I've ever acted on." He chuckled. "I'm an impatient man, and when it comes to shagging even less patient than I normally am." He grinned, what was they point after all? Sex was going to be brilliant no matter what they did before hand, so why delay that?
Sirius didn't mind that James didn't really have any fantasies of his own - he completely understood that, he had many fleeting thoughts about sex, but as soon as he was in bed with James it all left his mind because nothing else mattered.
"Thought you loved me, I can't believe you're threatening to ruin my reputation." He shook his head and grinned. "It is nice having time for this." Sirius agreed.