Ask her for a handjob
From Create Your Own Story
"Why don't you touch it and make sure your eyes aren't deceiving you?" you ask.
She tentatively reaches out with one finger, almost as if she is expecting your cock to bite her. You shiver as she touches it and runs her finger up and down the length. You take her hand and guide its fingers around your shaft, and that's when she really starts to get a clue about what she is to do. She may be dumb as rocks, but she is definitely experienced when it comes to handling boners.
While trying to keep your facial expression from giving anything away to the other passengers, you settle back and enjoy the sensation of her soft warm hand on your penis. She lets go long enough to cup your balls with her hand. That's when you notice her hand is already damp from your dripping precum.
Up and down, slightly twistining back and forth... you are on the verge of cumming hard.
Do you: cum in her hand?