Play with a black impotent Doberman until it's exhausted! It's a good dog but impotent

A black Doberman that's rarely played with, is an affectionate good dog
It really likes to rub against the owner, but it's one that can't get hard
And can't ejaculate, an impotent Doberman, this is so shameful!
The owner can only gently pat the good dog's head