She knows in general what to expect from her adventure but most likely prepared for pretty much anything and accepts everything that is coming her way, and in the process is getting really exciting which is pretty obvious from her facial expressions, sometimes pretty happy ones ;)
When she sticks her butt through the window she is trying to see what comes next and that creates composition similar to the picture on 1 dollar bill ;)
The entire video is 40 min long and full of excitement and action!

As he oils her down and rubs her firm, curvaceous body from top to toe her gentle moans are enough encouragement for him to lightly cup her pussy as he continues to knead her plump behind. Her body is slick perfection under the gentle lighting of the spa and George can hardly hold back as his soothing strokes power her erotic movements of blissful contentment.

Her pussy feels so good to the touch, he glides his fingertips over her again and again just to feel how her warm, inviting pussy moistens over him. His fingers take her to her first wild orgasm as she grasps her breasts in a flurry of excitement as what is next to come, she is so desperate to feel his cock inside her, filling her in a way she needs it most. He turns her on her back and gives her slick opening a generous lick before watching her fuck back on him, finishing by slowly pounding her into an orgasm of his own.