In a more modern - day setting, Pearl could be a mysterious object that Pitch comes across. He quickly becomes possessive of it. The Phantom, a shadowy figure, also has an interest in Pearl. It could be that Pearl has some sort of secret code or power source. The fanfiction could then explore how Pitch and the Phantom fight over it, with Pitch being over - protective of his newfound possession.
There might be a fanfiction where Pearl from Danny Phantom has an adventure with a character named Lemon. They could be on a quest to find a special artifact that has the power to balance the forces in their world. This would involve them facing various challenges and making new friends along the way.
For Pitch, you can make him more complex by giving him a backstory of why he's so possessive. Maybe he had things taken from him in the past. For Pearl, if it's a person or a sentient object, give it a unique personality, like being naive but with a strong will. The Phantom can be made mysterious. Don't reveal all about him at once, keep the readers guessing about his motives and powers.
A popular one is 'Pearl's Adventure with Pitch in the Danny Phantom Realm'. It follows Pearl as she gets dragged into the chaotic world of Danny Phantom and teams up with Pitch. The story has a great plot that keeps you on your toes, with lots of mystery and some really cool supernatural elements.
One possible plot could be that in a world full of chaos, Pitch, a dark and mysterious character, discovers a pearl that has magical powers. The lemon, which could be a symbol of something sour or difficult in this story, is the key to unlocking the full potential of the pearl. Fanfiction often takes existing elements and twists them in new ways, so perhaps Pitch has to face his own inner demons as he tries to use the pearl's power, with the lemon adding an element of challenge and mystery to the journey.
One idea could be a prequel focusing on how the Bellas formed in the first place. Maybe explore the early relationships between the members like Aubrey and Chloe.
One plot idea could be that the Barden Bellas somehow get caught up in a supernatural hunt. Maybe they're performing at a haunted location and strange things start to happen. The girls then team up with the Winchesters to figure out what's going on and stop the evil entity.
A crossover with 'High School Musical' would also be cool. Picture the Pitch Perfect girls and guys going to the same school as the High School Musical characters. There could be a big musical showdown where the two groups have to combine their talents. The Pitch Perfect crew's edgy acapella style might clash and then blend with the more traditional musical theater style of High School Musical, leading to an amazing performance.
Another plot could involve Rapunzel's hair having the ability to repel Pitch Black's nightmares. Pitch discovers this and tries to cut off her hair. However, Rapunzel uses her wits and the help of Pascal and Maximus to outsmart him. In the process, Rapunzel realizes she has more power within her than she ever knew, not just in her hair but in her spirit, and she becomes a force to be reckoned with against Pitch.
A possible plot could be that Yellow Pearl and Blue Pearl are tasked with finding a rare gemstone. During their journey, they face many challenges that force them to work together more closely than ever before. As they do, they start to understand each other's personalities better. For example, Yellow Pearl's efficiency and Blue Pearl's compassion complement each other. They might also encounter other characters who try to stop them from achieving their goal, which adds more drama to the story.
One plot idea could be that Hermione becomes overly possessive when Harry starts getting a lot of attention from other witches at Hogwarts. She might start using her intelligence to outwit those girls in a rather devious but humorous way, like tricking them into embarrassing situations so they'll stay away from Harry.