One possible plot could be that Tony and Natasha reunite in heaven. They might look back on their time on Earth, the battles they fought together. They could share their regrets, like Natasha might regret not being able to do more for the world before her sacrifice, and Tony might regret some of the decisions he made during the various conflicts. They then start to explore heaven together, meeting old friends who also passed away and reminiscing about their shared memories.
Maybe an old enemy from their time on Earth who somehow managed to get into heaven. This enemy could hold a grudge against both of them and wants to take revenge. They might use their knowledge of Tony and Natasha's past weaknesses to try and defeat them in heaven, where the rules are different from Earth.
One possible reason could be that Tony has some pre - existing biases. Maybe he has a set idea of the type of person he wants on his team and Natasha doesn't fit that mold in his mind. For example, if he's looking for someone with a more technical background and Natasha's skills seem more combat - oriented to him at first glance.
Another theme is teamwork. They are both part of the Avengers, so many fanfictions focus on how they work together on missions, whether it's fighting a new villain or rescuing hostages. Their different skills - Tony's technology and Natasha's espionage abilities - make for interesting team - up scenarios.
Natasha may come to view Tony as a kindred spirit. If she discovers that he also has a longing for real connection like she does, she'll feel a sense of kinship. His true nature might show that he is not as different from her as she initially thought. They could then develop a closer friendship or even something more, as they realize they share common emotional ground beneath their outward appearances.
One common theme is the blending of their two very different personalities. Tony is often portrayed as more flamboyant and tech - savvy, while Natasha is more reserved and stealthy. Their marriage forces them to find common ground and understand each other better.
One common theme is the fear of the unknown. Since they are both superheroes, they're not used to dealing with normal life events like pregnancy. Another theme is the support they give each other. For example, Tony might use his resources to ensure Natasha has the best medical care during pregnancy.
One great 'Tony Stark and Natasha Romanoff fanfiction' is 'The Unlikely Alliance'. It explores their relationship in a post - apocalyptic world where they have to rely on each other's skills to survive. Their banter and the way they gradually come to understand and respect one another is really engaging.
One common theme is trust. Since they are both Avengers with different backgrounds, building trust between them is often explored in fanfiction. For instance, in many stories, they start off being cautious around each other but gradually learn to trust completely.
One reason is that in the Marvel universe, they are part of the same team. So, there's a lot of potential for interaction. Their different personalities can create a lot of interesting dynamics. Natasha's care for Tony can be seen as a way to balance out his more reckless side. Also, fans love to explore the idea of characters who seem tough on the outside, like Natasha, having a soft spot for someone like Tony. It adds a layer of depth and emotion to their relationship that is fun to explore in fanfiction.