This is quite an interesting one then I have never heard of. It is also something I will never do. A dirty zorro is when after a guy is done banging a girl in the bottom, he takes his penis that is covered in...well you know, and writes his initials on her butt cheeks. First of all if you are going to have anal sex prepare yourself so this doesn't happen or you are just asking for it. But hey everyone likes something different so if this is your thing all the power to you.
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