Well, excluding the improper 'lemon' aspect, in Jon and Sansa fanfictions, family loyalty is a big theme. They come from the same family, and their loyalty to each other and to their family name can be a central part of the story. Also, the theme of redemption can be present. They both have had their share of hardships and mistakes, and how they redeem themselves through their relationship is an interesting aspect.
Rather than the 'lemon' - related themes, in fanfictions about Jon and Sansa, the theme of power dynamics is quite common. Sansa has learned a great deal about power during her time in King's Landing, and Jon has his own experiences with leadership. How they balance and interact with each other's power and influence within the North is often explored. Additionally, the theme of trust - building is there. Given their past and the complex situations they've been through, how they come to trust each other again is a fascinating theme.
Since 'lemon' content is inappropriate, we can talk about common themes in regular Jon and Sansa fanfiction. One common theme is their reunion. After being apart for a long time in the story, their reunion can be full of emotions. Another theme is their cooperation in ruling the North. They both have a deep connection to the North, and their joint rule is often explored.
One common theme might be the exploration of their complex relationship. Given their family ties and the history in the 'Game of Thrones' universe, fanfics might delve into how they overcome those obstacles in a romantic and often passionate way.
In Jon and Sansa lemon fanfics, a prevalent theme is the building of an emotional connection between them. This connection then leads to more physical expressions of love. Writers may also explore the theme of power dynamics within their relationship. Since they both have different positions of power in the original story, how these power dynamics shift or are balanced in a romantic relationship can be an interesting theme. Additionally, the theme of protection - Jon protecting Sansa or vice versa - is also quite common as it ties into their characters' natures in the original work.
Love and romance can also be a theme, not just in a romantic sense between them but also their love for their family, the North, and their people. And of course, there's the theme of survival. They both have to survive in a very harsh and dangerous world, and fanfictions show how they do that, sometimes relying on each other and sometimes on their own wits.
One common theme is the reunion. Given their separation in the original story, many fanfictions focus on how they come back together. Another theme is the exploration of their relationship in the context of ruling the North. Since they both have a connection to the North, it's often explored how they would do it together.
One common theme is family loyalty. Since they are both Starks, their loyalty to the family name and to each other as family members is often explored. For example, in many stories, they team up to protect the North and the Stark legacy.
One common theme is family. Their pregnancy often becomes a catalyst for bringing the family closer or dealing with family secrets. For example, in many stories, their unborn child makes the Starks reunite in a more meaningful way.
Love against all odds is also a big theme. Given their complex family relations and the political situations, their love is often portrayed as something that overcomes all these barriers. Another theme is political intrigue. Their marriage is a significant political move, and fanfictions often explore how they navigate the power struggles around them while maintaining their relationship.
One common theme is family reunion. Given their separation in the original story, many fanfics explore how they come back together and the emotions involved. Another is the rebuilding of Winterfell. They are both Starks and Winterfell is their home, so it's a central aspect in their relationship in fanfics.
A possible theme could be discovery. The lemon could be something new that Jon and Sansa discover together, and through that discovery, they learn more about themselves and each other.
One common theme is the rebuilding of the North. Since they both have strong ties to the North, many fan fictions focus on how they work together to restore it. Another theme is the exploration of their relationship against the backdrop of the political turmoil in Westeros. Love in a time of chaos is often depicted.