You think back to high school health class and think to your self, 'Yeah, humans do have a cloaca'. Oh wait, didn't you take a veterinary course instead of health? Whatever, it doesn't matter. You insert your penis into what you hope is your clone's cloaca. The body part that you chose to penetrate is what would be more traditionally be referred to as an anus.
"Oh, wow, that feels weird..." Your clone says. She seems to have been caught of guard by it.
"Bad?" You ask.
"Yeah, kinda, could you take it out?" She asks polity.
You consider her request, but instead you respond with. "Nope, I'm not doing that, CUZ' THIS FEELS FUCKING AWESOME!" You proceed to pound her ass.
She rolls her eyes and holds on for the ride. This feels amazing for you, she seems to feel the need to rub her vagina the whole time. In the mist of the sex and moaning, your faces come together, you stare deep into her eyes, which are identical you your eyes, and you fall deeply in love. You french kiss your clone while you two orgasm simultaneously.
Kissing her felt like kissing your sister. Hot.
Either way, that felt amazing. Though your collective inexperience looked pathetic and wouldn't make it on any porn site, you don't care about that. Why would you?
(Do I mark this as M/F sex or as self pleasuring? huh...)