You should also consider the relationships they already have in the original story. Harry is friends with Fred and George, but you want to build on that. Maybe have them share secrets or have an adventure that only the three of them can go on. It could be something like finding a hidden magical object in the Forbidden Forest. This would force them to rely on each other and deepen their bond. And don't forget to use vivid descriptions to bring the story to life.
You can start by looking on popular fanfiction websites such as Archive of Our Own (AO3). Just use the search function and type in 'George Harry Fred Slash'. Another option is Fanfiction.net. There, you can also search for relevant tags related to these characters.
Another theme is loyalty. In these fanfictions, they are often depicted as being extremely loyal to each other, even in the face of difficult situations. This loyalty is what holds their relationship together and helps them overcome various obstacles. They would stand by each other no matter what, whether it's dealing with school bullies or more serious threats from the wizarding world.
Begin by creating a plot. It could be something set during their time at Hogwarts or after they've graduated. For example, you could write about them going on a secret mission together and during that time, their feelings for each other start to surface. Also, don't forget to add some magical elements that are characteristic of the Harry Potter universe.
I'm not sure about specific 'Fred George Jealous Harry' slash fanfiction. You could try searching on fanfiction websites like Archive of Our Own. They have a vast collection of fanfictions, and by using the relevant tags and keywords, you might be able to find what you're looking for.
A really good one is 'Among the Marauders' Descendants'. It not only involves the relationship between Harry, Fred and George but also ties in elements of the Marauders' era. It creates a rich backstory and a vivid present - day narrative where the slash relationship between the three characters is developed in a very engaging and believable way.
Often, there might be a situation where Harry is oblivious to the feelings of Fred and George at first. So, the plot could revolve around how they try to make their feelings known to Harry without scaring him away. This could involve a lot of internal struggle for Fred and George, as they are also brothers and don't want to let their relationship with each other suffer because of their feelings for Harry. There could also be a sub - plot where other characters notice the tension between Fred, George and Harry and either try to help or make things more complicated.
There's 'The Trio's New Dynamic' which delves into how Harry's relationship with Fred and George changes the whole Gryffindor dynamic. In this fanfiction, they might be involved in some pranks that lead to more serious adventures and self - discovery. For example, a prank gone wrong could lead them to discover a hidden part of Hogwarts and in the process, their relationships grow stronger.
You could start with a scene at Hogwarts, like in the Great Hall. Fred and George are causing a bit of a ruckus, Harry is trying to stay out of trouble, and Remus is just watching with amusement. Then, Lucius arrives with some sort of business at the school, and Severus is there to greet him. This sets up the different personalities and the potential for conflict or cooperation right away.
When starting 'Harry Potter and Chad Slash Fanfiction', it's crucial to do your research. Read the original books again to pick up on small details. For Chad, you could base his character on different archetypes from the Harry Potter world. Maybe he has a bit of the Gryffindor's courage, the Ravenclaw's intelligence, or the Hufflepuff's loyalty. Develop their relationship gradually. Start with small interactions, like a shared class or a Quidditch match. As you write, keep in mind the flow of the story. Make sure the dialogue sounds natural and that the actions of the characters are believable within the context of the Harry Potter universe.
First, you need to be really familiar with both the Harry Potter universe and the Doctor's world. Know the characters, their personalities, and the rules of each world. For the slash part, think about which characters from the two universes you want to pair in an interesting way. Then, start with a simple plot idea, like the Doctor accidentally landing in Hogwarts and how he interacts with the students and staff, and gradually build the relationship between your chosen characters.