I think Quinn could be a great addition. She could be the one who initially misunderstands the situation between Sam and Rachel and causes some drama. Also, Finn could be included as he might have his own feelings about Rachel being with Sam.
Definitely Kurt. He could be the voice of reason for Sam and Rachel. Kurt has a lot of wisdom when it comes to relationships. And Mercedes too. She could offer support to Rachel and give her advice on what to do about her feelings for Sam. She might also be the one to encourage Sam to be more open about his emotions.
There are also those writers who have been around for a long time and have a large body of work. For example, 'glee_storyteller' might be considered one of the best. They often create unique scenarios for Rachel and Sam, like having them travel back in time to the golden age of Broadway and interact with the greats. Their writing is very vivid and engaging.
I think Santana would be a great addition. She could be the sassy friend who gives them brutally honest advice. Also, Brittany. She might be really excited for them and offer some really unique and endearing ways to help with the pregnancy, like knitting baby booties in really strange colors. Puck could also be included. He might start out as a bit of a troublemaker, teasing Sam about it, but then turn into a really good support for them.
One idea could be that after the kiss, they have to deal with the reactions of their friends. Some friends might be supportive while others could be jealous or shocked. Another plot could be that the kiss was part of a dare, but then they start to develop real feelings for each other and struggle with whether to pursue it further.
One common theme is the exploration of their relationship. Since they had a complex dynamic in the show, fanfiction often dives deeper into their feelings for each other. Another theme is their musical journey. Given that Glee is a musical show, fanfictions usually incorporate their singing and how it impacts their relationship, like writing duets for them. And finally, the theme of self - discovery is also present. As they both grow as individuals, they learn more about themselves through their relationship with each other.
Love is a very common theme. Since they are two main characters with a lot of potential for a relationship, many fanfictions explore their romantic feelings for each other. It could be a slow - burn love or a sudden realization of love.
Finn could be involved if the fanfiction wants to explore a relationship with him as the possible father. He was an important part of Rachel's life in the original series, and his reaction to the news would be significant.
Mr. Schuester might be included as well. As the teacher and mentor in the Glee club, he could offer guidance to Rachel during this difficult time. He might help her figure out how to balance school, the Glee club, and her pregnancy. Additionally, Mercedes could be a character involved, providing her best - friend - like support to Rachel, and being there for her through all the emotional ups and downs.
Finn is very likely to be involved. If he's the father, he would have a huge role in the story. He'd need to deal with his own feelings about becoming a father so young and how it affects his football and Glee club activities. Quinn could also be involved. She might offer Rachel advice based on her own experience with pregnancy, even though their situations were different. And of course, Mr. Schuester would be there. He'd be like a mentor to Rachel, guiding her through the tough times and making sure she still has a place in the Glee club.
There are also fanfictions that explore the 'secret relationship' trope. In the Glee universe where there are a lot of eyes on them in the glee club and at school, it can be exciting to write about them hiding their relationship from others. This trope adds an element of mystery and tension to the story.
One interesting plotline could be them collaborating on a big musical number for a school competition. They might start off with different ideas but then combine their talents to create something amazing.