I'm not aware of any such stories in mainstream science - fiction literature. Most science - fiction focuses on more positive aspects like exploration, technology, and inter - species relations in a non - sexual way.
We haven't discovered any real alien life yet, let alone any stories about the sexual behavior of alien octopuses. Most of these are just wild ideas in science - fiction novels or movies that are used to create strange and exciting scenarios.
These stories are often in the realm of science - fiction and conspiracy theories. In most cases, they lack scientific evidence. They might be a product of human imagination, perhaps influenced by the idea of the unknown nature of aliens and the fear of forced sexual encounters which are very disturbing concepts in our society.
No. Scifi sex stories can also be about post - apocalyptic scenarios where the rules of society regarding sex have changed completely. In a world where resources are scarce, relationships and sex might be more about survival and creating a new generation in a very different way than we know today.
One alternative is the exploration of alien cultures. We can see this in works like 'Dune' where the focus is on the unique culture, politics, and ecology of the planet Arrakis and its native species. Also, adventure - based stories involving aliens, like in 'Alien' (the first movie mainly), where the focus is on survival against a hostile alien species rather than any sexual or inappropriate themes.
These types of stories are likely the result of overactive imaginations, or in some cases, attempts to create sensational and attention - grabbing stories. In the scientific community, there is no serious consideration given to the idea of aliens performing such tests related to sex. The search for extraterrestrial life focuses on more plausible aspects such as the existence of habitable planets and the development of intelligent life forms.
No. They can also be found in some forms of independent filmmaking. There are independent movies that explore the concept of alien - human sexual encounters in a very creative and sometimes strange way.
One common theme could be the exploration of the unknown. Since aliens are, by nature, very different from humans, the stories might focus on how characters deal with this extreme otherness in a sexual context. For example, the differences in anatomy and mating rituals.
One common theme is the sense of powerlessness. The humans in these stories are usually abducted against their will and have no control over what happens. Another theme is the 'otherness' of the aliens, which often makes the sexual encounters seem very strange and abnormal compared to human experiences.