C. C. from 'Code Geass' could also be an interesting main character in this fanfiction. She has her own mysterious powers and knowledge. In 'Game of Thrones', she could be a sort of otherworldly figure, influencing the events from the shadows, perhaps even having an impact on the White Walkers or the dragons.
Lelouch would be a great choice as the main character. His strategic mind and Geass power would make him a formidable force in the world of 'Game of Thrones'. He could easily navigate the political minefield of Westeros.
A 'Code Geass' and 'Game of Thrones' fanfiction could be really exciting. It might combine the political intrigue of 'Game of Thrones' with the mind - controlling powers of 'Code Geass'. For example, Lelouch from 'Code Geass' could find himself in the middle of the power struggle in Westeros. He could use his Geass to manipulate the various lords and ladies, adding a whole new level of chaos to the already complex world of 'Game of Thrones'.
It could be a new character who is a mix of Naruto and Lelouch. He has Naruto's determination and Lelouch's intelligence. This character could be the center of the harem, with his unique personality attracting female characters from both universes.
It could be a combined force of Orochimaru and some of the power - hungry nobles from Code Geass. Orochimaru is always after power and knowledge, and the nobles in Code Geass are often corrupt. Together, they could create a really formidable enemy for the heroes.
Perhaps a character from Game of Thrones could obtain the Geass power. Arya Stark, for instance. With her skills as an assassin already, the Geass power could make her an even more formidable force. She could use it to exact revenge on her enemies more effectively, or to infiltrate enemy strongholds with ease. This would change the dynamic of her character arc significantly.
Arya Stark could be an interesting main character as a summoner. She already has a lot of skills like stealth and combat. If she were a summoner, she could summon the spirits of those she has killed to either help her in battles or to gather intelligence. It would be a new twist on her character.
Bran Stark could also be the main character. His new powers as the Three - Eyed Raven give him a whole new perspective. He could be the one to guide Westeros into a new era. He could use his knowledge of the past and his ability to see things that others can't to make decisions that would shape the future of the Seven Kingdoms.
A Skagosian outcast. He could have been banished from his tribe for some reason, like not following their brutal traditions. This character would be interesting as he would be an outsider even in his own land at first, and his journey to either regain his place or find a new one could be full of adventure and self - discovery.
Melisandre could be a main character if you consider her as a kind of warlock. She has her strange powers, like seeing the future in the flames. You could write a fanfiction exploring her past, how she became a red priestess and gained her powers, and her further adventures in Westeros, perhaps with her using her powers in different ways than in the original series.
It could be a Targaryen descendant. Since the Targaryens were known for their connection with dragons, it would make sense for one of their descendants to be the main character in a story about the last dragon.
It could be a young apprentice wizard who has just discovered his powers. He is eager to prove himself and protect the North from all the threats it faces.