A great concept for a Sailor Moon OC fanfic is an OC that has a special connection to the moon but not in the same way as Sailor Moon. This OC could have been created by an ancient civilization on the moon to be a protector. She might have different abilities like being able to control lunar phases for various effects, such as using a new moon to create a shield or a full moon to enhance her strength. Or an OC who is an artist, and she uses her art to fight the evil. Every time she draws something, it comes to life to battle the bad guys.
Well, you could do an OC who is a magical animal in the Sailor Moon world. Like a talking cat that has the power to transform into a human - like form. This OC could befriend the Sailor Scouts and help them out in unexpected ways. For instance, using its animal instincts to sense danger before the Scouts do. Also, consider an OC who is a lost princess from a forgotten kingdom in the Sailor Moon universe. She has to discover her true identity and her powers while teaming up with the Sailor Scouts to fight against the common enemies.
Another interesting concept is an OC who is a villain at first but later becomes an ally. Maybe they were brainwashed by the real villains. Their journey from the dark side to the good side can be full of drama, self - discovery, and interesting interactions with the Sailor Guardians.
One idea could be that the OC is a new senshi from a far - off planet who arrives on Earth just as a new threat emerges. The Sailor Scouts are initially suspicious but soon realize they need all the help they can get.
One idea could be a 'what if' scenario. For example, what if Sailor Moon had to face an enemy that could manipulate time in ways she'd never encountered before. Another could be a story focusing on the relationships between the Sailor Scouts outside of battles, like a day in their normal lives at school. And a third idea could be a crossover with another popular anime universe, such as having Sailor Moon meet characters from Naruto and how they would interact.
One idea could be a story where a new Sailor Guardian emerges from a different dimension and has a unique power that can either help or hinder the fight against the Black Moon Clan. For example, she might be able to manipulate time in a different way than Sailor Pluto. Another plot could involve a member of the Black Moon Clan who has a change of heart and decides to secretly assist the Sailor Guardians. This would create a lot of internal conflict within the clan.
One interesting idea could be a unique setting for the kiss, like on a magical moonlit balcony in the Crystal Tokyo. Another might be the emotions involved, perhaps a forbidden love between a Sailor Scout and an unexpected character, which adds a lot of drama to the fanfiction.
Well, in Sailor Moon dark fanfiction, a cool plot could be the Sailor Guardians facing an enemy that can manipulate their worst fears. This would make them question their own abilities and loyalties. Also, a story where the power source of the Sailor Guardians is somehow tainted, turning their powers dark and making them struggle to control it. Or perhaps a plot where a new dark Sailor Guardian emerges, with powers equal to or greater than Sailor Moon's, causing chaos in the magical world.
One idea could be a crossover with the Harry Potter universe. Sailor Moon and her friends could attend Hogwarts and have to deal with both magical threats from the wizarding world and the dark forces they usually face. For example, they might help the students at Hogwarts fight off a new kind of dark magic that has similarities to the dark energy they combat in their own world.
One idea could be that the Sailor Scouts somehow end up in the SVTFOE universe. They could team up with Star and Marco to fight a common enemy. Maybe an evil force that combines the darkness from both universes.
One idea could be that the characters from RWBY end up in the Sailor Moon universe and have to learn the ways of the Sailor Scouts. For example, Ruby could be intrigued by Sailor Moon's transformation and try to adapt her Crescent Rose to work in that magical world.
An interesting plot could be that Goku and Sailor Moon meet during a multiverse tournament where representatives from different anime universes are competing. They initially don't get along because of their different fighting styles and beliefs, but as the tournament progresses, they realize they can learn from each other. Together, they face off against a cheating opponent who is using unfair tactics to win. Through their combined efforts, they not only defeat the opponent but also learn to respect each other's worlds and ways of fighting.