A common theme is forbidden love. Since Ben is often in a world full of rules and regulations about interacting with different species, a love story between him and an alien that is not allowed by some authority can be very appealing.
Some popular themes could be adventure. Since Ben 10 is often about going on exciting adventures, in fanfiction with Ester, they might go on quests together. Another theme could be friendship. They could start as acquaintances and develop a deep friendship over time. And also, there might be themes of self - discovery. As they face different challenges, they learn more about themselves and their capabilities.
One popular theme could be alternate universes where the characters have different powers or relationships. For example, an AU where Ben has to deal with his powers in a more adult - like world full of political intrigue related to the Omnitrix. Another theme might be character growth and development into adulthood, like how Gwen would handle her magical powers as an adult in a more complex society. And also, there could be themes of love and relationships, perhaps exploring Ben's romantic relationships in a more mature way compared to the original series.
One popular theme is their adventures together. Fans often write about them exploring new places and facing strange creatures, just like in the original series. Another theme could be their relationship development, whether it's strengthening their bond as cousins or having some friendly arguments that lead to character growth.
Some fanfictions focus on the baby Ben 10 characters being taken care of by other characters. It could be an older version of one of the main characters or a side character who has to babysit them. This leads to all sorts of comical situations as they try to keep the baby versions of the heroes out of trouble. There are also themes about the baby characters' first encounters with new aliens in a more cutesy and less dangerous context compared to the regular Ben 10 stories.
Some fanfictions might revolve around the idea of alternate universes. In these stories, Ben and Gwen could have different relationships or roles. For instance, Gwen could be the one with the alien device and Ben could have different powers or no powers at all. Another theme could be family - how they deal with family issues while also being superheroes or dealing with their special abilities.
One popular theme could be alternate universes where the characters have different powers or relationships. For example, an AU where Ben's alien forms have unique social structures among themselves. Another theme might be character growth and development into adulthood, dealing with more complex emotions and responsibilities compared to the original series. Also, crossovers with other science - fiction universes can be a theme, like Ben 10 meeting characters from Star Trek.
One aspect of Ben 10 love story fanfiction could be the unique pairings that fans create. For example, they might pair Ben with an alien character he has encountered. This adds a new dimension to the story as it explores relationships in a different universe.
Well, their relationship in the official story is complex and full of potential. Fans are attracted to exploring the 'what - ifs'. What if they had more time together? What if they could fully explore their feelings without all the external conflicts? Fanfiction allows for that exploration.
One popular theme is their relationship development. Fans love to read about how their love grows and overcomes obstacles. Another is adventure, like them going on quests together. For example, in many fanfictions they might go on a magical adventure to save Auradon or the Isle of the Lost.
One popular theme is the 'forbidden love' aspect. Since Mal is from the Isle of the Lost and Ben is the king of Auradon, their relationship can be seen as something that goes against the norm in their world, which makes for an interesting and often explored theme.