Dog Lips 

An expression or analogy used to descripe the labial (lips) region of the female vagina, when purple on the inside and brownish black on the exterior.

"Yo,that bitch is so loose her snatch looks like dog lips."

Dog Lips by pitchc February 19, 2008

dog lipstick 

When a dog gets sexually excited, it's cock grows, much like a humans. However, a dog's erection often resembles a lipstick tube, scarlet in colour.

"Look Pete! That dog's got it's dog lipstick out again!"

dog lipstick by RyDav. March 8, 2009