One common theme could be the adjustment to the new situation. Both Rouge and Knuckles would need to adapt to the idea of becoming parents. Another theme might be the protection of the unborn child. Since they are often in a world full of action and danger in their original stories, this would be an important aspect.
There could be a theme of sacrifice as well. They might have to sacrifice some of their previous ways of life, like their solo adventures or their more carefree attitudes. And also, how they come to terms with the fact that their lives are now centered around this new family they are creating.
I'm sorry, I don't have specific fanfiction stories to recommend directly. You can try searching on popular fanfiction platforms like Archive of Our Own or FanFiction.net. Just type in 'Rouge and Knuckles pregnant' in their search bars and you'll likely find relevant stories.
In fanfiction, Knuckles is often depicted as a strong and stoic character. He's known for his loyalty to his duties, like guarding the Master Emerald. Rouge, on the other hand, is usually portrayed as a sly and cunning character, with her thieving skills being a prominent part of her character. Their interactions can range from friendly banter to tense rivalries, depending on the plot of the fanfiction.
You can try fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions on various topics including Sonic the Hedgehog related ones where Knuckles and Rouge are characters. Just use their search function and look for the specific tags related to pregnancy and these two characters.
One popular type is adventure - based fanfiction. For example, there could be a story where Knuckles and Rouge team up to find a lost ancient relic. They have to overcome various obstacles and enemies in their path.
It could be about how they first realized their feelings for each other. Maybe during an adventure, they find themselves relying on each other more and more, which eventually leads to their marriage.
The potential for growth in their relationship. Knuckles is a bit of a stoic character, and Rouge is full of charm and guile. In fanfiction, writers can explore how Knuckles learns to open up and show his softer side because of Rouge. And Rouge can find a sense of loyalty and true connection with Knuckles that she may not have had before. Their relationship can be a journey of self - discovery for both of them, which is really appealing in fanfiction.
Yes, there are. You can find some on fanfiction websites like Archive of Our Own. Just search for 'knuckles and rouge love' and you'll get a bunch of results.
A sense of isolation is sometimes a theme. Rouge may feel isolated as a vampire, different from her previous self and those around her. And Knuckles may also feel a sense of isolation in trying to deal with Rouge's situation on his own, without fully understanding the vampire world. This creates a complex emotional landscape in the fanfictions.