The plot could involve a mind - control situation. Some villain tries to control Supergirl, but Flash manages to break the control. In the process, they have a deep emotional connection and kiss. This would show Flash's heroism and how it affects their relationship.
One plot could be that they are both training together and accidentally use a new power that links their minds. Through this link, they start to see each other's true feelings and memories. This new - found understanding leads to a kiss, and then they have to figure out how to deal with their relationship while still being superheroes.
There are some really interesting Flash and Supergirl kiss fanfictions out there. One that I liked had them in an alternate universe where they were the only ones with powers and they had to rely on each other more. Their relationship developed gradually and the kiss was a really sweet moment in the story.
The plot could revolve around an alternate universe. In this universe, they are not superheroes in the same way. Artemis is more of an artist and Kid Flash is just a regular guy with a love for speed. They meet in a more normal setting, like a coffee shop. As they get to know each other over time, their relationship develops and the kiss is a natural progression of their growing feelings.
In a 'Supergirl meets the Flash fanfiction', they might team up to fight a powerful common enemy. For example, a super - villain who can manipulate time and space, and only their combined powers can stop him.
If Barry kidnapped Supergirl in fanfiction, it could be a really interesting plot twist. Maybe Barry has been affected by some sort of red kryptonite - like substance that makes him act out of character. This would lead to a conflict between the Flash and Supergirl's friends and allies. They would be confused as to why Barry would do such a thing.
A Naruto and Supergirl kiss fanfiction could start with some sort of interdimensional rift or magic that brings them together. Maybe Naruto is on a mission in his world and accidentally gets sucked into Supergirl's universe. They initially don't understand each other due to their different languages and cultures, but through non - verbal communication and a series of adventures together, they develop a connection. Eventually, in a moment of high emotion, like when they save each other from a powerful enemy, they share a kiss.
One plot idea could be that they kiss accidentally during a high - stress mission and then have to deal with the awkwardness and new - found feelings. Another could be that they've secretly liked each other for a long time and the kiss is a long - awaited moment of confession.
In this fanfic, the plot could be really interesting. Since it's a crossover, there could be a unique blend of the Supergirl and Flash universes. Kara's pregnancy might be a catalyst for a big change in the story. For example, it could lead to a new form of power or ability within Kara that is related to motherhood. Flash could be the one to first notice the changes in Kara's powers because of his quick thinking and observational skills. The story might also involve a race against time as they try to protect Kara and the unborn baby from a villain who wants to use the baby's potential powers for evil purposes.
In a 'Team Flash meets Supergirl' fanfiction, there could be an epic team - up. The Flash might use his super speed to save Supergirl from a kryptonite - powered trap. Then they could join forces to fight a common enemy like Lex Luthor or an alien invasion. The scientific minds in Team Flash could also help Supergirl understand some new aspects of her powers.
One idea could be that a powerful villain from another dimension is causing chaos in both Supergirl's and the Flash's cities. They have to team up, with Supergirl using her strength and flight to combat the villain's minions on a large scale, while the Flash uses his speed to disrupt the villain's energy sources. Maybe they also discover a connection between their powers that helps them defeat the villain in the end.
In a fanfiction, there could be an alien race that is immune to Supergirl's powers but is vulnerable to the speed force. Flash discovers this during a battle where Supergirl is struggling. He then uses his speed to create a barrier around the aliens, trapping them long enough for Supergirl to figure out a new way to defeat them, like using her super - breath in a new way that Flash helps her direct with his speed.