One common theme is redemption. Since Riley left under some not - so - great circumstances, a lot of fanfics focus on him redeeming himself in Buffy's eyes. Another theme is second chances. Fans often write about them getting another shot at their relationship.
Well, often there's the theme of the unexpected. Given their lives filled with fighting demons and all, pregnancy might be a very unexpected turn. Also, there could be themes related to their insecurities. Riley might worry about being a good father considering his own past and Buffy might worry about protecting the baby from all the evils around. And of course, there could be themes about their relationship evolving in new ways because of the pregnancy.
Common themes include the duality of their natures. Buffy is a hero, and Angelus is a villain, yet they are drawn to each other. The theme of secrecy also pops up often. Their relationship can't be out in the open easily. Lust is a very obvious theme considering the 'lemon' nature of the fanfiction. But there are also themes of sacrifice, where either Buffy or Angelus might have to sacrifice something for the other or for the greater good in the context of their relationship.
One common theme is the exploration of their forbidden love. Buffy and Spike's relationship was always a bit taboo in the original series, and in fanfiction, this is often magnified. Another theme is the power struggle between them, which adds an extra layer of tension to their passionate encounters.
Since I don't promote or encourage lemon (explicit) content, I can't really say about the common themes in such fanfiction. But in general, in normal Xander and Buffy fanfiction, common themes include their friendship, their shared experiences in fighting vampires and other supernatural beings, and the growth of their relationship over time.
One great Buffy and Riley fanfiction is 'Riley's Redemption'. It delves deep into Riley's character after his departure from the show, exploring his growth and his lingering feelings for Buffy. Another one could be 'Buffy and Riley: A New Beginning' which imagines a scenario where they reunite under different circumstances and have to face new threats together.
A common theme is the exploration of their forbidden love. Since Spike is a vampire and Buffy is a slayer, their relationship is taboo in the Buffyverse, and fanfictions often play on this aspect. Another theme is passion and desire, which is where the 'lemon' part comes in.
Love and friendship are likely to be common themes. Since it's a fanfiction about two characters, the development of their relationship, whether it's a romantic love or a deep friendship, could be a central focus.
There are many alternatives. For example, fanfiction that focuses on their friendship. It could explore how they supported each other during battles or difficult times in the Buffyverse. Another alternative is adventure - based fanfiction, where Buffy and Riley go on quests together to fight evil without any sexual undertones.
Yes, there are likely some Buffy and Riley pregnant fanfictions out there. You can try searching on popular fanfiction websites like Archive of Our Own or FanFiction.net. Just use the relevant tags to narrow down your search.
Adventure is also a popular theme. Their characters might be put in exciting scenarios, like exploring a mysterious place or going on a quest. This makes for an action - filled and engaging read. For instance, they could be on a journey to find a lost treasure or save a magical creature. In these stories, their individual skills and the bond between them are usually highlighted.