For those of you who are larval SF authors, I am pleased to offer the Alpha Game One-Minute Writer's Workshop on how to write intersexual relations in science fiction and fantasy.
1. Determine if you a Male author or a Female Author.
2a. If you are a Male author, the female character should surprise the male protagonist by impaling herself on his sexual organ for no apparent reason. The male protagonist should duly indicate his humble gratitude and undying loyalty to said female character for the rest of the novel, or, in the case of multiple books, series.
2b. If you are a Female author, the female protagonist should rapidly attract the undivided attention of two handsome alpha males with oversized genitalia who are nevertheless different in some nominal manner. She should have ecstatic sex with both of them, separately, with absolutely no consequences to her or anyone else. Due to her inexplicable, but supremely attractive qualities, her inability to choose between her two lovers neither results in any negative consequences beyond some minor emotional drama nor causes either of them to move on to other women. The female protagonist should duly indicate her agony over being unable to decide between the two men while alternately having sex with both of them for the rest of the novel, or, in the case of multiple books, the series.
3. Publish and profit!
Do not worry that the intersexual relations described in your novel(s) bear no similarities to any actual human romantic relations in recorded history. This is science fiction, after all, and per Dirty Uncle Hugo, your prime literary directive is to portray the world as you think it ought to be.