One possible cause could be political intrigue. In the world of Westeros, Cersei has many enemies. Perhaps a rival noble family finally manages to outmaneuver her in the power games, leading to her demise. For example, they might stage a coup and execute her.
In some fanfiction, Jaime's character might develop into a more remorseful figure. His relationship with Cersei could be a source of internal conflict, and he could start to question his loyalty to her more deeply, leading to a change in his actions and decisions.
Jaime Lannister could be a main character. Given their complex relationship, his reaction to Cersei's early death would be a significant part of the story. He might be filled with guilt, or perhaps relief depending on how their relationship had developed in the fanfiction.
Sansa Stark could be an interesting pairing. It could be a story of two strong - willed women from opposing sides. They could either become bitter enemies or, in a more creative take, find common ground and form an unexpected alliance. Also, Margaery Tyrell is a great character to pair with Cersei. Their power struggle in the show was fascinating, and fanfiction could take it in new directions, like Margaery actually befriending Cersei and showing her a different way to rule.
I think 'cersei and sansa fanfic' can be really interesting. It often explores the complex relationship between two very different characters. In many fanfics, they might start as enemies but develop a more nuanced connection over time. Maybe there's a plot where they have to work together against a common enemy in the Seven Kingdoms.
One of the main events was her rise to power. Cersei managed to take the throne after her son's death. She also had many conflicts with other powerful characters like Margaery Tyrell. For example, she plotted against Margaery which led to Margaery's downfall. Another significant event was her walk of atonement which was a very humiliating experience for her but also showed her resilience in a way as she was able to come back from that and continue her fight for power.
The plot of a 'naruto is cersei's son fanfic' might involve Naruto being an outcast in Westeros due to his different appearance and abilities. Cersei might initially be ashamed of him but later realizes his potential. Naruto would have to navigate the complex social hierarchy of Westeros. He could introduce concepts like chakra and ninjutsu, which would be completely foreign to the people there. His friendship with characters like Tyrion could be a key part of the story as they both are different from the norm in their own ways. And he might end up in a battle to save Westeros from a great evil, using his Naruto - like determination and skills.
It's possible that such a fanfic exists in the depths of the internet. Fanfic writers often come up with the most unexpected pairings and storylines. If it does exist, it would probably be a very interesting read, although it might also be a bit controversial as it combines two very distinct fictional universes. The writer would have to deal with the different magic systems, cultures, and character traits from both 'Harry Potter' and the world of Cersei in 'Game of Thrones'. They would need to find a way to make Harry's character fit into the new context of being Cersei's son, perhaps by exploring how his upbringing in a new, combined world would affect his personality and abilities.
One interesting plotline could be an alternate universe where Jaime decides to fully turn against Cersei much earlier. He might expose her secrets to save the realm from her tyranny, leading to a complex power struggle within King's Landing.