It was late, and Alison was drunk.
That sentence could be used to describe every other day, but not tonight. Tonight that sentence had meaning. It would be an explanation in the morning, and it would leave both of them sour.
But Sarah didn't mind. It started out with "Thanks for taking care of me." and ended with Alison's hand slowly covering Sarah's, pulling her into a gentle kiss.
Sarah would wake up to her arms around Alison, they'd fall asleep together in the most innocent way. And the moment would be tainted by "Never again." she was sure. But neither of them ever could forget, no matter how hard they tried to make the memory vanish.