It wasn't said with regret, not this time. Crowley's incapable of regret at the moment. Everything they've every done, right or wrong, brilliant or foolish, virtuous or sinful or just plain ineffable, has led them here to this moment, and this moment is perfect. This is moment is everything he wants.

"Holding you to that, too," Crowley mumbles happily, he hand on Aziraphale's back slipping down to blatantly grope at his arse for a moment. "Holding you to everything. 'Specially to me."

It's a ridiculous sentence and he doesn't care. He's half asleep while wound a naked, approving, adoring Aziraphale and the world is as good as it's ever been.