In an all - grown - up Monsters Inc fanfic, the world itself could have evolved. There could be new technologies for scaring or collecting energy. The characters might have to adapt to these changes. And if Boo is all grown up and involved, she could bring a human perspective that helps the monsters improve their scaring business in unexpected ways. Maybe she could introduce new concepts from the human world that the monsters had never thought of, like different ways of using sounds or lights for scaring.
Another idea is that all the characters are now parents themselves. They have to balance their work at Monsters Inc with raising their own little monsters. It could show how they use their experiences as scared kids or scarers to be better parents.
It could be about Boo using her experiences in the monster world to make a difference in the human world. Maybe she becomes an advocate for better understanding between humans and monsters.
By showing how her time in the monster world influenced her values. For example, if she learned about kindness from Sully, as an adult she could be extra empathetic.
Well, they could have a really wild adventure. Maybe the KH characters would be confused at first in the world of Monsters Inc. Sora might try to fight the monsters thinking they are Heartless. But then they could realize that the monsters are just trying to do their jobs. Kairi could make friends with Boo easily, and Riku might be intrigued by the technology in the monster world.
A possible plot could be that there's a baby monster that is scared of everything in Monsters Inc. Boo, who has experienced the monster world, takes it upon herself to show the baby that there's nothing to be afraid of. She introduces the baby to all the friendly monsters she knows. Sulley and Mike are a bit skeptical at first but soon see how Boo's kindness is helping the baby grow braver. As time goes on, the baby becomes more confident and starts to explore the world on its own with Boo by its side as a guide.
They could fit in by using their skills. The keyblade wielders could protect the monsters from any real threats. And the Monsters Inc crew could teach the KH characters about their own form of energy, screams. It's a simple exchange of what they are good at.
A great Monsters Inc bedtime story could be about the first time Sulley met Boo. Sulley was on his regular job of scaring kids when he accidentally let Boo into the monster world. At bedtime, Sulley was worried about what to do with Boo. But as he spent time with her, he realized she was not scary at all. Instead, she was a sweet little girl. Sulley then made a little bed for her out of soft monster fur. He told her a story about the stars in the monster sky, which were actually made of the leftover energy from the kids' dreams. Boo fell asleep listening to this story, and Sulley learned that there was more to humans than just screams.
Monsters Inc. is set in a world where monsters generate energy from children's screams. But as the story progresses, we discover that laughter can generate even more powerful energy, leading to a major shift in the monsters' way of doing things.
It could be about Calvin becoming an artist. He might use his wild imagination from his childhood adventures with Hobbes to create unique and thought - provoking artworks. Maybe he has an exhibition where all his works are inspired by the days of building forts and having snowball fights with Hobbes.
The fanfic might explore how the world of Beetlejuice has changed over time. It could introduce new rules or elements in the afterlife or the living world. For instance, new types of ghosts or supernatural entities could be introduced, and the grown - up characters have to deal with them in ways that are different from when they were younger. Also, the fanfic could delve into the backstories of the characters more deeply, now that they have more life experiences to draw from.