Sex and sexuality in speculative fiction

Sexual themes are frequently used in science fiction or related genres. Such elements may include depictions of realistic sexual interactions in a science fictional setting, a protagonist with an alternative sexuality, or exploration of the varieties of sexual experience that deviate from the conventional.

Science fiction and fantasy have sometimes been more constrained than non-genre narrative forms in their depictions of sexuality and gender. However, speculative fiction also offers the freedom to imagine societies different from real-life cultures, making it an incisive tool to examine sexual bias and forcing the reader to reconsider his or her cultural assumptions.

Prior to the 1960s, explicit sexuality of any kind was not characteristic of genre speculative fiction due to the relatively high number of minors in the target audience. In the 1960s, science fiction and fantasy began to reflect the changes prompted by the civil rights movement and the emergence of a counterculture. New Wave and feminist science fiction authors imagined cultures in which a variety of gender models and atypical sexual relationships are the norm, and depictions of sex acts and alternative sexualities became commonplace.

There also exists science fiction erotica, which explores sexuality and the presentation of themes aimed at inducing arousal.

As genres of popular literature, science fiction and fantasy often seem even more constrained than non-genre literature by their conventions of characterization and the effects that these conventions have on depictions of sexuality and gender. Science fiction in particular has traditionally been a puritanical genre oriented toward a male readership. Sex is often linked to disgust in science fiction and horror, and plots based on sexual relationships have mainly been avoided in genre fantasy narratives. On the other hand, science fiction and fantasy can also offer more freedom than do non-genre literatures to imagine alternatives to the default assumptions of heterosexuality and masculine superiority that permeate many cultures.

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Wikipedia