Finger her

You can feel the capitulation in Samantha as you expose her lust. You smile, but you don't want to rub it in that you were right. It's her pussy you want to rub.

You coat your fingers with Samantha's pussy juices and then you forcefully pull her legs farther apart. Then you get to work rubbing her clit with your fingers.

It's much easier to rub her clit while driving than it is to digitally penetrate her, so you're able to get a nice, steady movement going.

Samantha closes her eyes and leans back and you pleasure Samantha as well as you can without crashing the car.

"That's right, Samantha, give yourself over to me," you say, encouraging her to embrace the pleasure. "You don't want to resist me. You're gonna do what your boss says aren't you?"

"Yessir," she says, opening her legs a little more.

"You're gonna cum on your boss's fingers aren't you?" she nods and bites her lips. "You want to cum for me, Samantha. To show me how much you want me."

Suddenly Samantha's body shakes and she firmly grabs your hand by the wrist and holds it in place between her legs. Samantha is cumming on your fingers just as you told her to.