Well, it would be a really wild and interesting scenario. In fanfiction, anything can happen. Harry Potter brings his wizarding world knowledge and magic, while Supergirl has her super - powers. They might have a very unique wedding ceremony in Vegas. Maybe Harry would use magic to create some amazing effects during the wedding, and Supergirl could fly around showing off her powers. Their life together would be full of adventures, like fighting bad guys with a combination of magic and super - strength.
In a Vegas - set Harry Potter and Supergirl fanfiction, it could be a story of a magical tournament held in Vegas that attracts wizards from all over, including Harry Potter. Supergirl, intrigued by the strange magical happenings, investigates. They form an unlikely friendship as they both try to keep the peace during the tournament which is being targeted by some anti - magic groups who want to expose and destroy the wizarding community.
Maybe Harry Potter uses his magic to create some amazing illusions on the Vegas Strip, and Supergirl is both amazed and a bit concerned about the chaos it might cause. She helps him keep things under control while also having fun with the new magical experiences.
He could marry a Muggle he meets by chance in Vegas. Maybe a singer or a waitress who has a big heart and an open mind towards the strange things Harry might do or say because of his wizarding background.
A 'Harry Potter marries Supergirl' fanfiction might start with Supergirl accidentally landing in the wizarding world. Harry Potter, being the curious and brave wizard he is, approaches her. At first, there are misunderstandings due to their different cultures and powers. But as they start to communicate and learn about each other's worlds, they realize they have a lot in common. They both fight for the good of their respective worlds. This mutual understanding leads to a deep friendship and later, love. Their marriage would be a grand event, attended by wizards, witches, superheroes, and supervillains (the ones who are allowed to come under a truce). It would symbolize the coming together of two very different yet equally amazing fictional universes.
In some versions of this fanfiction, the Vegas part could be a parallel dimension that Harry accidentally stumbles into. There, he discovers a different set of rules and meets a person who is his soulmate in that dimension. Since he has always been a bit of a rule - breaker and a hero, he decides to marry this person despite the differences. It could also be that the story is a comical take on Harry's life, where he goes to Vegas with Ron and Hermione for a lark, and things go hilariously wrong and right, resulting in him getting married.
Well, in a 'Harry Potter Marries in Vegas' fanfiction, it could start with Harry being frustrated with the wizarding world's formalities regarding relationships. He goes to Vegas for a break and gets drunk. There, he meets a girl who seems to understand his struggles. They have a wild night and end up at a wedding chapel. After the marriage, he has to figure out how to incorporate her into his life in Hogwarts or wherever he is living at that time. Maybe she has some magical abilities he doesn't know about at first.
I'm not sure of a specific 'Harry Potter Marries Vegas' fanfiction off - hand. But you can start by looking on popular fanfiction websites like Fanfiction.net or Archive of Our Own. Just use those keywords in their search bars and you might find some interesting stories.
To develop this fanfiction story, we could explore the cultural differences between the wizarding world and the super - hero world. In Vegas, they might have a wedding that combines elements of both worlds. After the wedding, they could go on adventures. Maybe they encounter a villain who is a mix of a dark wizard and a super - villain. Harry and Supergirl have to use their combined skills and powers to defeat this new threat. And as they face these challenges together, their relationship grows stronger.
One idea could be that Supergirl, while on a mission in a different dimension, accidentally lands in the wizarding world of Harry Potter. She is initially confused by the magic there as it's different from her own powers. Harry and his friends are both in awe and a bit wary of her. They could team up to fight a common enemy that threatens both the wizarding world and the world Supergirl is from.