Power is a common theme. Both Cersei and Daenerys are power - hungry in their own ways in the original series, and fanfics often explore how they either compete or cooperate regarding power. For example, in many fanfics, they fight over who will rule Westeros.
Writing or seeking adult fanfictions involves inappropriate and often unethical content. It's better to focus on the positive aspects of the original characters in the official works, such as their leadership, their growth throughout the story, and their relationships that are suitable for general audiences.
In such a fanfiction, they might initially be hostile. Daenerys, with her dragons and army, could pose a huge threat to Cersei. Cersei, being the shrewd and power - hungry character she is, would likely try to outwit Daenerys. Maybe there would be some intense verbal sparring between them as they both try to assert their dominance over King's Landing.
One great 'cersei daenerys fanfic' is 'A Meeting of Queens'. It explores an alternate scenario where Cersei and Daenerys have to form an alliance. The author does a wonderful job of depicting their complex personalities and the power dynamics between them.
One possible plot twist could be that Cersei pretends to surrender to Daenerys. Daenerys, believing her, takes Cersei into her confidence. But Cersei is actually plotting a big betrayal from within. She could be secretly gathering her remaining forces and planning to assassinate Daenerys when the time is right.
One idea could be a fanfiction where Cersei and Daenerys meet in a diplomatic summit. They start off as rivals, but gradually come to understand each other's motives and the difficult positions they are in. They might end up forging an uneasy alliance against a common threat, like the White Walkers in the original series.
Well, a simple idea could be that the pregnancy is a secret at first. Only a few close allies know. Jon and Daenerys have to be very careful to keep it that way. They might have some close calls where the secret almost gets out, adding a lot of tension to the story.
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.
There could be characters like Tyrion. In many Game of Thrones - related stories, Tyrion is a complex and important character. He might interact with Daenerys in the fanfiction, perhaps becoming one of her advisors in her gaming - inspired adventures.
Sometimes, characters like Arya Stark are paired with Daenerys. Arya's skills as an assassin could be used to eliminate key targets in Daenerys' revenge plan. Their combined strength and determination would make a formidable force against their enemies.