Earlier in the episode, Rory told her mother that despite all the hot and heavy make out sessions with her boyfriend, she is far too busy to be thinking about sex. It didn’t seem very believable at the time, and now she admits the truth – she is thinking about sex with Jess, or at least she is considering it as something that is likely to happen if they stay together. She promises to talk to Lorelai before anything happens.
The Annotated Gilmore Girls 