One possible plotline could be a more metaphorical 'pregnancy' in the sense of Orochimaru creating or nurturing a new and powerful jutsu or experiment that is like a 'baby' to him. It could show his obsessive nature in a different light, as he devotes all his time and resources to this new creation.
Maybe in an alternate universe, Orochimaru has a partner and they are expecting a child, but the story focuses on how Orochimaru's past and his thirst for knowledge impact his approach to fatherhood. For example, he might be worried about passing on his dangerous or unethical ways to the child and has to struggle with his inner demons to become a better parent.
Another plotline could be that Orochimaru discovers a pregnant woman with some unique power or ability. Instead of his usual malevolent intentions, he decides to protect her out of scientific curiosity. He wants to study how her pregnancy and the unborn child's potential power interact, but in a non - harmful way, and throughout the story, he gradually changes his view on life and relationships because of this encounter.
A possible plotline could be Orochimaru's redemption. He realizes the error of his ways and joins Naruto in protecting the ninja world. He could use his vast knowledge of jutsu and forbidden arts to help Naruto against new threats.
Perhaps Naruto starts to have a connection to Orochimaru's other experiments or creations. He might find himself in a situation where he has to either help or fight these other 'products' of Orochimaru's mad science. Also, the fanfiction could explore how Naruto's friends react to what has happened to him. Do they trust him still? Or are they afraid of what Orochimaru might have turned him into?
A plot could be that Orochimaru, seeking redemption in a way, starts to train Sakura in some unique and dark arts that he has mastered. Sakura, with her determination to become stronger, accepts this training but struggles with the moral implications. This could lead to an internal conflict within her as she tries to balance her new - found power with her values. Another possibility is that Orochimaru places a curse on Sakura for some reason, and she has to find a way to break it. In her quest to break the curse, she delves deeper into Orochimaru's lair and discovers more about his true motives and plans. Or perhaps Orochimaru kidnaps Sakura to use her as a bargaining chip against Sasuke. But Sakura uses her wits and ninja skills to not only escape but also turn the tables on Orochimaru, showing him that she is not to be underestimated.
One possible plotline could be Batgirl dealing with her pregnancy while still trying to protect the city. She might have to balance her new physical state with her crime - fighting duties, and rely more on her allies.
One possible plotline could be a magical or supernatural occurrence that leads to the pregnancy in a non - sexual way. For example, a spell gone wrong or a unique power interaction.
One possible plotline could be about the challenges Reshiram faces during pregnancy. For example, how it adjusts to its changing body and powers. Another could be the reactions of other Pokémon characters in the story, whether they are supportive or not.
One possible plotline could be the challenges she faces during her pregnancy. Maybe she has to deal with the reactions of her friends and family within the fandom's world. Another could be how she manages her normal duties or adventures while being pregnant.
One possible plotline could be how Nami and the other Straw Hat crew members react to her pregnancy. Maybe they would be overly protective or excited. Another could be about Nami dealing with the physical and emotional changes during pregnancy while still being part of the crew's adventures.
One possible plotline could be that Tinkerbell's pregnancy is a magical accident. Maybe she was exposed to some strange magic that caused this unexpected situation. Another could be that she is in love with a fairy or a character from the Peter Pan universe and they are starting a family together.
A possible plotline could be that at first, they are shocked by the pregnancy but then gradually accept it and start planning for their future together.