A prevalent theme could be Thor's growth. In some fanfictions, Thor might have reached a point where he realizes that his leniency towards Loki has only led to more problems. So, he decides to take a tougher stance, which includes physical confrontation. This can show Thor evolving from a more naive and forgiving brother to a more assertive protector of Asgard.
One common theme is family. Their brotherly bond, whether it's strained or strong, is often explored. Another theme is redemption, especially for Loki as he has made many mistakes. Also, power and how they both deal with it, Thor with his more straightforward use and Loki with his more cunning approach, is a frequent theme.
It's difficult to pinpoint the most popular authors for this very specific type of fanfiction. Fanfiction is a vast and diverse world. There are probably many talented writers out there creating these stories, but they may not be widely known as a whole. You might find some great authors by joining Marvel - related fan groups on social media. People in those groups often share and recommend their favorite fanfictions and the authors who write them.
One common theme is redemption. Female Loki might be trying to redeem herself in Thor's eyes or in the eyes of Asgard. For example, she could have made some mistakes in the past and is now on a path to make amends.
One common theme is redemption. Thor's overprotectiveness can be seen as a way to help Loki redeem himself in the eyes of the Avengers. For example, he might shield Loki from criticism so that Loki can focus on proving himself good. Another theme is family. Thor's actions show that he values Loki as family despite their past differences. It's like he's saying that family sticks together no matter what.
A very frequent theme is the comical aspect. The contrast between Thor's seriousness and baby Loki's mischievousness leads to many humorous situations. For instance, baby Loki might steal Thor's food or use his limited magic to play tricks on Thor, like changing his hair color.
Another theme is the exploration of their deep - seated feelings for each other. Fanfictions often dig into the complex emotions that Thor and Loki have had for each other throughout their history in the original mythology and how those emotions develop into love in the context of marriage.
One common theme is redemption. Loki often has a lot to atone for, and Thor's comfort can be a step towards his redemption. For example, in many fics, Thor's acceptance of Loki despite his wrongdoings starts Loki on a path of self - improvement.
One common theme is the clash of cultures. Hermione comes from the wizarding world, while Thor and Loki are from Asgard. This often leads to interesting situations as they try to understand each other's ways.
The theme of family loyalty often shows up. Thor feels it's his duty to protect Loki because they are family. Also, the power dynamics in Asgard can be a theme. Thor's overprotectiveness can be influenced by his position of power and his need to keep Loki, who is sometimes seen as a bit of a wild card, in check.
The theme of power and responsibility also pops up. With Thor being the more responsible and power - holding one, and Loki being the more mischievous and power - hungry at times, fanfictions play around with how they balance these aspects in their relationship. For instance, there are stories where Loki has to learn to handle power from Thor in order to protect Asgard.