One popular theme is the relationship between Julie and the phantoms. Fans often explore how their friendship might develop into something more romantic. Another theme could be the backstories of the phantoms. Maybe how they died and what their lives were like before becoming ghosts. Also, there are fan fictions that focus on the band's rise to stardom, like the challenges they face and how they overcome them in the music world.
Julie is definitely one of the most interesting. She has such a complex character, with her love for music and the loss of her mother that she's dealing with. Writers can explore her growth as a singer and as a person. The phantoms are also great. Luke, for example, with his passion for music and his mysterious past. There's a lot to unpack about how he became a phantom and his dreams for the band.
Music is a key element. It's what brings Julie and Luke together. Another is their shared dreams. They both want to make great music. And also, the connection that seems to go beyond the physical world, since Luke is a phantom.
One popular story could be about the phantoms getting to perform in a huge international music festival within the fanfiction world. It gives them a chance to show their music to a much wider audience and there are all kinds of new characters introduced like famous music producers who are wowed by their talent.
Julie is definitely a popular one. She's the main character and her relationship with the phantoms is central to the story. The phantoms themselves, like Luke, are also very popular. His backstory, his passion for music, and his growing relationship with Julie make him a great focus. Also, Flynn is often a key character in fanfiction as she's Julie's best friend and provides a lot of comic relief and support.
One great Juke fanfiction could be about their first date after the events of the show. They might go to a local music festival and share their dreams while enjoying different bands.
One idea could be that the phantoms discover a new power that allows them to interact more fully with the real world, like being able to touch objects for longer periods. Another could be a time - travel plot where they go back to the era when they were alive and have to deal with their past selves. Or perhaps a plot where Julie has a dream that predicts a danger to the phantoms and she has to figure out how to prevent it.
You can start by looking on fanfiction.net. It has a large collection of fan - created stories, including many for Julie and the Phantoms, especially those focusing on Juke.
You can try Archive of Our Own (AO3). It has a large collection of fanfictions for all kinds of shows, including Julie and the Phantoms. There are many different tags and filters you can use to find the specific type of fanfiction you're interested in.