Either go Bottom, Switch or Top. Tops protect their buttholes. Then you start learning the combat system.
Jump in, read the skills and fiddle about. Don't feel worried about save-scumming. It's a good way to practice the systems.
Never really knew there was a build like that, I'm generally all over the place. I don't know most of what's exactly going on with the sex mechanic except that well, its sex.