One interesting aspect could be the melding of different magical systems. In 'Harry Potter', there's a more structured magic with spells and wands, while 'Game of Thrones' has a more mysterious and often darker form of magic. Fanfiction might explore how characters from both universes interact with these different magics. For example, a wizard from 'Harry Potter' might be baffled by the magic of the Red Priests in 'Game of Thrones'. Another aspect is the clash of different cultures. The noble houses of Westeros and the Hogwarts houses have their own unique cultures and values. Fanfiction could play around with how characters from one set of houses interact with those from the other. It could also be interesting to see how the power struggles in 'Game of Thrones' play out in the context of the magical world of 'Harry Potter'.