A sense of humor.
Because they find him very down to earth.
She couldn't find any mooovers.
A helium polymer. HeHeHeHeHe
A very dry sense of humor
In 200 years the milk will have developed a culture.
They are both run by red-headed clowns.
Because gingers don't have Souls.
Because they have no soul
Because they take everything, literally....
Because he higher and higher. (I translated the joke from Dutch, and yeah it's supposed to not make any sense, it just sounds funny, in Dutch at least. :-$)