Another theme is sacrifice. Since they are in a dangerous world of 'Game of Thrones', they might have to sacrifice personal desires for the greater good. Fanfictions often show how they make tough choices regarding their family and the North.
The main characters are Ned Stark and Ashara Dayne. Ned is a noble and honorable man from House Stark, known for his loyalty. Ashara is a beautiful and mysterious woman from House Dayne.
One great 'Game of Thrones Robert Arryn Fanfic' is 'The Rise of Robert Arryn' which shows his growth and development in a more positive light. It gives him some agency and intelligence that he didn't really get in the show.
One possible fanfiction could start with Robert Baratheon as a young man. He is full of ambition and dreams of a united Westeros under his rule. He trains hard in combat, his sword becoming an extension of himself. He meets his future friends, like Ned Stark, during these formative years. They share tales around the campfire and make grand plans for the future. As he grows older, he participates in battles, his victories making him more and more renowned. His charisma draws people to him, and soon he is seen as a natural leader. But with power also comes temptation, and he has to face the challenges of politics and intrigue that come his way.
In 'Game of Thrones', Sansa is Ned's daughter. There is no sexual relationship between them in the official story as it goes against the nature of their family relationship. The show adheres to a certain moral and narrative structure.
One simple way in fanfiction could be through some kind of magic. Maybe there's a powerful red priestess who discovers Ned's body before it's fully decomposed. She uses her magic to resurrect him, much like Thoros of Myr did with Beric Dondarrion. Once back, Ned could play a major role in the political games again, this time with more knowledge and a thirst for revenge against those who wronged him and his family.
Well, in some fanfictions, Ned and Ashara could be involved in a love triangle with another character. This would add a lot of drama. For example, if there was a misunderstanding between them because of this third person, it could lead to heartbreak and tension. Also, perhaps they worked together to uncover a conspiracy in King's Landing, which put their lives at risk but also strengthened their bond.
One great Ned and Catelyn fanfiction is 'A Winter's Love'. It delves deep into their relationship before the events of the series. It shows their courtship and how they came to love each other, with beautiful descriptions of the North.