One common theme is the couple's journey to acceptance. They might be initially scared or in denial about the pregnancy but then gradually come to terms with it. Another theme could be the changes in their relationship. For example, they may become closer as they face this new challenge together. Also, preparing for the baby, like setting up a nursery or choosing a name, is often a theme.
Sure. In some fanfictions, the family reactions are a big part of the plot. If Luke and Sophia are from different backgrounds, their families might have different expectations. Sophia's family may be more traditional and have concerns about how they will be perceived in the community. Luke's family, on the other hand, might be more liberal and be immediately accepting. The family reactions can also drive the relationship between Luke and Sophia forward, either bringing them closer together as they face difficulties as a couple, or causing tension if the families don't get along.
I haven't come across a 'Luke Gets Percy Pregnant' fanfiction myself. Fanfiction writers can come up with some really wild ideas, but this one seems rather extreme. It might not be in line with the general tone or themes of the source material. That being said, the fanfiction community is full of surprises, so it could potentially exist on some less - known platforms or in some very specific corners of the larger fanfiction world.
In the fanfiction, one big challenge could be adjusting to their new roles. Sophia might struggle with leaving her job or hobbies to take care of the baby full - time. Luke may feel pressured to be the sole breadwinner. Also, they could face family - related challenges. Maybe their families have different ideas on how to raise the baby, which can cause conflicts.
Their relationship could develop through mutual support. Since they are having a baby together, they would need to be there for each other. For example, Luke could be there for Jessie during her morning sickness.
The fanfiction might explore their relationship transformation during the pregnancy. Luke could become more protective and responsible, while Emma might discover new strengths in herself. Their friends could also play different roles, some being very supportive and others causing some drama, which all adds to the story.
One possible plot could be that they face a lot of challenges. Maybe they are in a world full of danger and they have to protect their unborn child. They might need to find a safe place to stay, away from their enemies. Thalia could be using her skills to keep them safe while Luke tries to figure out how to provide for their future family.
One common theme is the anticipation and excitement. It's about looking forward to the new life that's coming. Another theme is the support system, like how their friends and the Jedi community rally around them.