Society in general could be an antagonist. If Maura and Frankie are in a situation where their pregnancy is not fully accepted, like in a very conservative community. The pressure from society to conform to certain standards and not have a baby at their stage in life can be a major obstacle for them.
Maybe Maura's over - controlling mother could be an antagonist. She might try to force Maura into making decisions she doesn't want, like giving the baby up for adoption against Maura's will.
One possible plot could be that Maura and Frankie are in a relationship and the unexpected pregnancy throws their lives into chaos. They might have to deal with family reactions, like Frankie's family being overjoyed while Maura's is more hesitant. And they start to plan for their future together, including finding a new place to live.
Another theme is the relationship changes. The pregnancy can bring a new level of closeness or some challenges to their relationship. They might have different ideas about parenting styles, which could lead to some conflicts but also opportunities for growth and understanding.
One great fanfic could be one where Frankie and Maura's journey through pregnancy is filled with humor and a lot of heartwarming moments. For example, they might deal with crazy pregnancy cravings together and support each other through the mood swings. It could also show how their friends and family react to the news, adding more layers to the story.
Friendship could be a common theme. Maybe they go on adventures together, support each other through tough times, and have a deep bond that is explored in the fanfiction.
The Brotherhood of Mutants could also be antagonists. They might view the pregnancy as a sign of the X - Men becoming too domesticated and vulnerable. They could launch attacks on the X - Mansion in an attempt to disrupt Rogue and Logan's new - found family situation.
Maybe there are some traditionalists in their world who don't approve of their relationship or the pregnancy. These people could be the antagonists, constantly trying to break them apart or cause problems for them.
One potential antagonist could be a group of rogue ninjas who see Sarada's pregnancy as a sign of weakness in the village. They might try to target her to cause chaos. Another could be a jealous rival who doesn't like the attention Sarada is getting due to her pregnancy and her connection to Naruto.
Frieza or his remnants could be antagonists. They might see the unborn child as a potential threat in the future, especially if it has strong Saiyan powers. So they could plan to attack Bulma to prevent the birth.
The Vicious 6 could be the antagonists. They might see Gru's preoccupation with Lucy's pregnancy as a weakness and try to take advantage of it. They could plan to kidnap Lucy to get to Gru and force him to give up his new - found family life and return to his old villainous ways.
Some of the power - hungry Underlanders who oppose Luxa's rule could be antagonists. They might try to use her pregnancy as a way to undermine her authority. They could spread rumors or create unrest, believing that with Luxa being pregnant, she is in a weaker position to lead, and they could try to take over the throne.