Pleased, Lydia smiled and nodded. "Good. Ground rules, then," she said, holding up one finger. "Rule number one: this is just sex for the sake of conception. This isn't a thing..."
She paused before continuing and holding up a second finger. "Two: I'm still probably going to have sex with other men afterward until I'm too disgusting for anyone to want to sleep with because I still need someone to build me a shelter and bring me food and make sure I don't end up dead, since we've established that your forte is intellectual, like mine, and neither of us is fit to do that for me."
Lydia held up a third and final finger, "and three: you have to promise that you can look at this from a clinical standpoint, because I want what I want, but I don't want it at the expense of our friendship. That will always come first. ...still with me...?"