Maybe the plotline focuses on the cultural differences that the OC brings to Sansa's wedding. For example, if the OC is from Dorne, they might introduce new traditions such as a different style of wedding ceremony or unique wedding gifts. This could cause some intrigue and also some conflict as the Northerners are not used to such things. Also, the OC could be a healer who discovers a plot to poison Sansa during the wedding and has to race against time to save her, all while falling in love with her charm and strength.
The OC could introduce new ideas to Sansa. For instance, if the OC is well - traveled, they might share stories of different cultures and ways of life that make Sansa more open - minded. This could help her grow out of her more sheltered view of the world.
Another development could be that their wedding sparks a series of events that change the power dynamics in Westeros. The union of a Stark and a Lannister, even an unwanted one like theirs, could cause other houses to re - evaluate their alliances. Some might see it as an opportunity to ally with this new 'power couple' while others might view it as a threat and plot against them.
At first, it would be very tense. Sansa is a Stark and Tyrion is a Lannister, and she was forced into this marriage. But over time, they could start to understand each other. Sansa might see Tyrion's kindness beneath his Lannister exterior.
A 'Game of Thrones' future fanfic might explore the consequences of the events in the original series. For instance, if Jon Snow's true identity becomes widely known, how would that reshape the political landscape? Some might see him as the rightful heir and support his claim to the Iron Throne, while others might oppose him out of fear or self - interest. Also, the White Walkers' threat might not be fully over, and there could be a resurgence of the undead in a different form.
In a 'Game of Thrones Afterlife' fanfic, the afterlife could be a place where different houses coexist in harmony or chaos. The Starks, Lannisters, and Targaryens could be engaged in a new kind of power struggle. This time, it's not about the Iron Throne but about something more ethereal, like control over the fates of the living. Their old rivalries and alliances might be re - evaluated and new relationships could form as they navigate this strange afterlife realm.
One interesting Sansa fanfic could be about her journey to become a more powerful leader in the North on her own terms. It might explore how she uses her wits and the lessons she's learned throughout the series.
One possible plotline could be that Robb manages to escape with a small group of his most loyal men. They then go into hiding, perhaps in the North, and start planning their revenge against the Freys and Boltons. Robb might also try to gather more allies, like the remaining Stark bannermen who are still loyal to him.
In a 'Tyrion and Sansa pregnant' fanfic, the plot might revolve around the relationship between the two. Maybe at first, they are not on good terms, but the pregnancy forces them to re - evaluate their feelings for each other. They could face challenges from society, as their union might be seen as strange or unacceptable. The fanfic could also explore how they deal with the medical aspects of the pregnancy in a medieval - like setting, with limited medical knowledge. And perhaps they end up having to flee to protect their child from those who would harm it, leading to a journey full of adventures and self - discovery.
One possible plotline could be the political fallout. Given their families' history and the power dynamics in the world they live in, their child could be seen as a threat or an opportunity by different factions. Another could be the emotional journey of Sansa and Tyrion. They might have to face their own feelings towards each other and the responsibility of raising a child together.
Common themes in these fanfics include the corruption of innocence. Sansa starts as a somewhat innocent girl, and Littlefinger's influence is a form of corruption. Her journey to resist that corruption is a big part of the story. Another theme is the search for identity. Sansa is trying to find out who she really is in the midst of all the chaos and Littlefinger's manipulations. And finally, the theme of loyalty is there. Sansa has to decide where her loyalty lies, whether it's with Littlefinger for a time or with her own family and the North. Littlefinger, on the other hand, has no real loyalty except to his own power - hungry self.