And why would the grandfather resist? When else would he have such an opportunity. Besides, it's always easier with a temperamental woman - she gets herself turned on and therefore comes much faster. You would have tried to bring to orgasm phlegmatic fat girl with a huge hollow. That's the kind of woman you should run away from. I've been in the middle of one of those, you can't wish it on the enemy.
And as usual with interracial sex it involves a white girl and a black guy. It's no surprise, by the way. Seeing him wielding his big trunk, satisfying both of them at once, it becomes clear why there's such an interest from black lovers.