"I know this," Lily said, as she gave his cock a squeeze.
"I know that every time I end up in your lap, you get hard as a rock for me. And I may not know, but I'm going to take a really good guess, that no one has made you come in a really long time, except for yourself."
The movement of her hand sped up, jacking him off properly now, instead of just teasing.
"So, I'll make you a deal. You come for me right now, spill it all over my hand, and no one needs to know. I swear, I won't tell a soul."