This guy is displaying incredible restraint. I for one would quickly devolve into a mindless savage slamming away on the young pussy, nuts swinging in all directions and sweat running down my ass crack like a raging river.
Grandpa had the first meaningful erection that he's had in 30 years. Gramps might need a belly full of Viagra to get even a hint of a boner with his wife. But...throw him a hot young fuck like Anneliese and he'll drive railroad spikes with it. Good score old timer.