There might be a fanfiction where Tommen discovers a hidden power within himself. For example, he has the ability to communicate with animals. This new power helps him to better understand the needs of his people and make more informed decisions as king. He could use this power to gain the loyalty of his subjects in a unique way.
Some fanfictions might center around Tommen's marriage to Margaery. It could be a story where they actually work together to bring peace and prosperity to the Seven Kingdoms. They could form an alliance against the other power - hungry lords and ladies and make real changes in Westeros.
One common theme is friendship. Many stories feature an OC becoming friends with Tommen and guiding him through the difficult political situations in King's Landing. Another theme is love. There are fanfictions where an OC falls in love with Tommen, which can range from a sweet, innocent love to a more complex relationship. Power dynamics is also a theme, as Tommen is a king and the OC's position relative to his power is often explored.
Yes, there are quite a few. You can start by looking on fanfiction.net or Archive of Our Own. Just search for 'Tommen Baratheon OC' and you'll find a variety of stories. Some might focus on Tommen's relationships with original characters in different scenarios, like during his time as king or his interactions within the court.
One common theme could be self - discovery. Since Tommen is a character from a complex world, in gay fanfics, he might be on a journey to understand his own sexual orientation. Another theme could be forbidden love, considering the political and social structures in his fictional world. Also, some fanfics might explore how his relationships could change the power dynamics around him.
There might be some out there. You could start by looking on fanfic platforms like Archive of Our Own. However, the availability and quality can vary. Some fanfics might focus on exploring different aspects of Tommen's character in a gay relationship context, while others could be more about creative reinterpretations of the world he's in with a gay relationship angle.
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.
One interesting fanfiction could be one where Renly Baratheon survives and forms a different alliance. Maybe he teams up with the Starks against the Lannisters, which would completely change the power dynamics in Westeros.
Love and loyalty also feature prominently. An OC Baratheon might be torn between loyalty to their family and their love for someone from another house. This creates a lot of internal conflict and interesting plotlines. In some stories, an OC Baratheon's loyalty to a friend or a romantic partner can change the course of events in the political landscape of Westeros.
In fanfiction, their relationship could develop through shared experiences. Maybe they both witness a great tragedy in the kingdom, like a massacre or a plague. This shared trauma could bring them closer together. They might start to work together more closely, with Tommen using his position to give his sister a platform to influence the court, and she using her wits to help Tommen make better decisions. Their relationship could also be complicated by the power dynamics at play, with some nobles trying to use their relationship to their own advantage, which they would have to navigate together.