Tyrion's loyalty to his own ideals and the people who side with him, like Varys, has a huge effect. When they work together, they are able to manipulate the political situation in King's Landing to some extent. Their loyalty to each other, even in the face of danger, changes the course of events. It also shows that loyalty doesn't always have to be based on family ties as in the case of the Lannisters.
The loyalty of the characters in their respective 'harems' greatly impacts the story. For example, Daenerys's loyal followers help her build her power. Jorah's loyalty, despite his past mistakes, gives her an experienced adviser. His unwavering support allows her to make more informed decisions. Missandei's loyalty provides her with a connection to the people she wants to rule. Their combined loyalty is a major factor in her rise.
Some characters in the harem might use their charm and beauty to gain an edge in the power struggles. They flatter the powerful men and use their influence over them. Others might form alliances with other harem members. By joining forces, they can have more power collectively. And then there are those who rely on their intelligence. They gather information and use it as a weapon to outmaneuver their rivals.
They also influence character decisions. Take the story of the Mad King. Jaime's knowledge of his father's role in the downfall of the Mad King affects his relationship with his family and his own actions throughout the series. These internal stories shape the characters' beliefs and values, which in turn drive the main plot forward in different directions.
Daenerys and Drogo's relationship was different. Through her relationship with Drogo, Daenerys gained an army and started her journey towards power. Her sexual relationship with him was part of her initial step in building her own empire. She learned how to use her femininity and the power she had in that relationship to start amassing her own forces and influence.
Sibling relationships within the Stark family, for example, are a major part of the plot. When the Starks are scattered, the bond between the siblings is a driving force. Arya's desire to avenge her family and Sansa's attempts to survive in King's Landing are related to their sibling ties. Their relationship gives them strength and a sense of purpose in the face of great adversity.
When it comes to Daenerys Targaryen in alternate history fanfiction, if she had landed in Westeros earlier, she would have faced different challenges. Her dragons would have been a bigger shock to the existing powers. Her character might not have had as much time to develop her leadership skills in Essos, but she would have to quickly adapt to the complex politics of Westeros. This would change how she interacts with characters like Jon Snow. Maybe they would be allies from the start instead of having the mistrust that developed in the original story.
An OC Stark might be more politically astute than the original characters. They could form different alliances, like making a deal with the Iron Bank that gives the North more financial power and influence. This would shift the power dynamics not only in the North but also across Westeros. The original plot of various houses vying for the Iron Throne would be affected as the North becomes a stronger and more independent force.
The complex and multi - faceted characters in 'Game of Thrones' are a huge inspiration for fanfic writers. For instance, Jaime Lannister's character arc from a seemingly villainous knight to a more morally ambiguous figure provides a rich ground for fanfic exploration. Writers might create scenarios where Jaime makes different choices, which in turn could be interesting for the characters themselves to watch if they could. His relationship with Cersei and Brienne are also ripe for fanfic reinterpretation.
Jon Snow might be included as well. His noble and brooding nature can add an element of mystery. In a harem fanfiction, he could be the object of many characters' affections, and his presence might stir up rivalries and alliances among the harem members.
Jon Snow is also quite popular. His mysterious parentage and noble nature can be used in interesting ways in harem fanfictions. For instance, he could be a character that many in the harem are attracted to, or he could be the one who has to navigate the politics of the harem while dealing with his own destiny.
Harry is the central figure. For the Game of Thrones side, Tyrion Lannister could play a role. He might befriend Harry or try to manipulate the situation for his own gain. In terms of the harem, Cersei could be an unexpected addition. Her power - hungry nature could create a lot of drama within the harem. Also, Brienne of Tarth could be involved, perhaps as a protector or a member of Harry's inner circle.