[M4F] New scientific study proves humans can't drink cow's milk and women's milk actually makes you live longer. So now every woman in the family have to be the family cow. I'm your brother and the practice soon turns sexual.

I have a very dutiful sister who would do anything for her big brother. It's actually pretty common that your tits will be out at the breakfast and dinner table in case someone needs milk. But then I want to drink straight from your nipples, I didn't account for how tisch it would turn us on.