Why does my boyfriend hurt our kitten flicking him really hard ?

Oh honey child, the question here ain't why does your boyfriend hurt your pets, but why do you stay with that piece of shit! Dump that psychopathic loser and move on with your life! Don't question why he does those awful things, but instead realize that anyone who abuses animals is a piece of shit psychopath. Understand that his behavior is an indicator of his pathology. People who abuse animals go on to abuse people, it's a proven fact! He'll eventually start hurting you. A person like him is not someone you can marry, and have children with, because he will abuse your children and that is certain. There is no future in this relationship, and you should leave him immediately! DO IT NOW, LEAVE HIM NOW!!!

REMEMBER HE'S A PIECE OF SHIT! Everyday after breakfast, coffee and cigarette I flush something more precious and valuable than your boyfriend down into the city's sewer. Now it's your turn, flush that piece of shit out of your life, girl!