One idea could be exploring Percy's internal struggle as he fades away. Maybe he's dealing with a curse or some sort of magical exhaustion that's causing this fade. He could be trying to tie up loose ends with his friends and family, having deep and emotional conversations.
You could also write a fanfiction where Percy's fade away is a ruse. He pretends to fade to draw out an enemy that has been targeting him. He secretly works with his friends to set a trap while they all think he's disappearing. This would add an element of mystery and intrigue to the story.
First, think about the reason for Percy's fade away. Is it something supernatural? Or is it related to a personal sacrifice? Once you have that, start with a scene that sets the mood. For example, if it's a supernatural cause, you could start with Percy noticing strange things around him like objects disappearing or his reflection fading. Then introduce the other characters' reactions to his situation.
One idea could be a fanfiction that focuses on what happened to Haku after Chihiro left the spirit world. Maybe he had to face new challenges or make difficult choices. Another could be a story about Chihiro returning to the spirit world as an adult, but finding it completely changed. And a third idea could be a fanfiction that delves into the backstories of the minor spirits we saw in the movie, like the soot sprites and how they came to be in the bathhouse.
One idea could be a crossover with 'Alice in Wonderland'. Chihiro could find herself in Wonderland and have to navigate through the strange rules and characters there, while also using her experiences from the Spirit World. Maybe she'd meet the Cheshire Cat who could be as mischievous as some of the spirits she met in Spirited Away.
One idea could be a fanfiction where Percy and his friends go on a new quest in a modern, urban setting. Instead of the usual mythological locations, they have to deal with monsters hiding in big cities. Another idea is a story that focuses on the relationships between the characters in a more in - depth way, like exploring the friendship between Percy and Grover during their off - quest times. And a third idea could be a time - travel fanfiction, where Percy gets sent back to the time of the ancient Greek heroes and has to interact with them while still holding onto his modern values.
One idea could be to explore Percy's life after he has fully mastered his powers. Maybe he goes on a quest to find a long - lost relative who also has demigod powers. Another could be a story where Percy and his friends have to deal with a new type of monster that is immune to their usual weapons and they have to find a creative way to defeat it.
One possible plot could be Percy's struggle against the power that seals him away. Maybe he has to find a way to communicate with his friends on the outside to get help. Another could be the discovery of the true motives behind his seclusion.
The 'fade away novel' could be a genre or a specific work. If it's a genre, it might deal with themes of loss, decline, or impermanence. The story could involve the fading away of a hero's powers, or the slow disappearance of a magical realm. If it's a specific novel, without more context, it's hard to say exactly what it's about, but it's likely to center on some form of 'fading away' whether it's physical, emotional, or spiritual.
I'm not sure of a specific 'fade away novel' off the top of my head. However, some novels that have elements of fading away could be 'The Great Gatsby'. In it, the dreams and illusions of the characters fade away as the story progresses. Another could be 'The Catcher in the Rye' where Holden's innocence and his view of the world seem to fade as he experiences more of life.
One plot idea could be Percy having to team up with Hera to rescue a group of demigods who have been captured by an ancient monster. Hera, despite her usual aloofness, realizes she needs Percy's unique skills.
One interesting aspect could be the exploration of characters' emotions in more depth. In 'bleach fade to black fanfiction', authors might delve into the hidden fears and desires of the characters that weren't fully explored in the original series. For example, they could show how a character copes with the loss of a power or a loved one in a more personal and detailed way.