At first, their interaction would likely be very guarded. Sansa would be cautious as she has learned to be in a world full of danger. Tywin would probably see her as a young, naive girl but also a valuable asset. As time goes on, Sansa might start to challenge Tywin's ideas, which could lead to some intense exchanges between them.
Arya and Tywin could also interact in a more unexpected way. Maybe in a situation where they are forced to work together for a short time due to some external threat. During this time, Arya has to constantly remind herself of her ultimate goal of revenge while Tywin is constantly on guard against her, yet also seeing potential in her skills for his own purposes.
One common theme is revenge. Given Oberyn's fate in the original story, many fanfictions explore his thirst for revenge and how he might go about achieving it.
There might be some Oberyn Cersei fanfiction out there, but the 'lemon' aspect makes it a bit tricky. Fanfiction websites usually have rules against explicit content. You could try looking for more general Oberyn Cersei fanfiction that focuses on their power dynamics, their possible interactions given their characters in the show or books, rather than seeking the 'lemon' type which is likely to be hard to find in a legitimate and clean - cut way.
There is a fanfiction called 'Oberyn's Quest'. It follows Oberyn on a journey across Westeros where he uncovers some long - forgotten secrets. The story does an excellent job of staying true to his character, his determination and his cunning nature, making it a great read for Oberyn Martell fans.
Yes, there are quite a few. Some explore Oberyn Martell's journey in the Harry Potter universe. For example, there are fanfictions where he might be a visiting wizard from a different magical land and gets involved in the Hogwarts affairs. You can find them on popular fanfiction websites by using relevant tags.
One common theme could be forbidden love. Given the setting in which Oberyn Martell exists, a gay relationship might be frowned upon in that society, adding an element of secrecy and danger to the story.
One common theme is the clash of their different worlds. Arya is a young, vengeful girl from the North, while Tywin is a powerful, calculating lord from the Westerlands. Their interactions often explore this contrast.
There are several good ones. 'Tywin's Ascent' is a fanfic that details his rise to power. It gives a lot of background on his family and the challenges he overcame. 'The Mind of Tywin' is really interesting as it tries to get into his thought process. It shows how he made decisions that shaped the Westeros we know. And 'Tywin's Last Stand' is a fanfic that imagines his final days in a very creative way.
Character development is a key element. Writers often focus on how Aryia's vengeful side and her Stark upbringing interact with Tywin's Lannister pride and his political ambitions. For example, in some fanfics, Aryia's skills as a fighter might be pitted against Tywin's strategic mind in a tense showdown.