is a womans pussy that is always leaking dog sperm. When she has sex with a male dog, the dogs penis forms a big 'knot' (before the male dog ejaculates, the penis swells up to make the vagina clamp down on its penis, at the base of the penis a bulb is formed to 'lock' the penis into the human vagina) to stop all the semen from gushing out. After ejaculation the dog is 'tied' to the human female for about an hour to ensure 'proper' impregnation. So much semen is ejaculated (500ml for mastiffs) that it floods the entire womb. Women find this quite satisfying as the temperature of the semen is significantly higher than a humans body, so she'll feel warm inside. Over the next few days the semen absorbes through the womb and you get semen leakage from the vagina.
Some males dogs get pussy from pregnant women. When the dog ejaculates all the semen gushes into the womb all over the baby.
Fuckin hell Susan it's been days since that that Mastiff fucked you and you're still leaking cum. I'm not gonna have sex with you until you clean your dog pussy out.
The dog filled me up real good. He came so much. I felt all that cum skwirt inside me into my womb. His sperm is going to be swimming around in my body.