The act of defecating inside the vagina of a menstruating woman, which gives the turd a red hue. Expel it from the vagina afterwards and if it is in tact, you have yourself a port mackerel, also known as, a turd covered in tomato sauce.
Baby you make me so horny, I want to give you a port mackerel.
by GunaDK June 25, 2015
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