Perhaps Danny's sneeze is the result of a curse placed on him by a vengeful ghost. This curse could start to change him in unexpected ways, like making him more ghost - like or losing control over his powers. This would be a major turning point as he has to find a way to break the curse and return to normal, all while facing the challenges that come with these changes.
If Sebastian sneezes at a crucial moment, like when he's about to fight an enemy, it could make him seem vulnerable. This could change the enemy's perception of him and make the fight more interesting. For example, the enemy might think he's weak and become overconfident.
You can start by checking out fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'Danny Phantom' and then sort by the ratings and reviews. The ones with high ratings and positive reviews are likely to be high - quality.
In some fanfictions, Danny's mom might find out when she accidentally witnesses Danny transforming into his ghost form. Maybe she walks in on him at a crucial moment.
He could be a secret helper. Danny can secretly assist the 911 operators by using his powers to gather information about emergencies that normal means can't detect. For instance, he can see through walls to find trapped people and then relay the information to the 911 dispatch.
It might be a large, open space with floating platforms and ramps. The walls seem to be made of a translucent, ghostly energy that shimmers and pulses. There are holographic displays showing maps of Amity Park and the surrounding areas, as well as data on different ghosts Danny has encountered. There are also areas for Danny to relax, like a small corner with a worn - out couch and a mini - fridge filled with ecto - coolers.
In Danny Phantom fanfiction, heat might affect Danny in various ways. For example, his ghost powers could be weakened as some fanfics might play with the idea that extreme conditions like heat disrupt the balance of his human - ghost hybrid state. It could also make it harder for him to stay invisible or intangible as his energy is being sapped by the heat.
Danny would probably be heartbroken. He really cares about Sam, so finding out she cheated would be a huge blow. He might go into a state of denial at first, not wanting to believe it.
Perhaps Danny turns into a dragon in a completely unexpected situation, like during a school event. His sudden transformation causes chaos and he has to quickly fly away to avoid being seen. In the process, he discovers that he can access new areas in his dragon form that were previously inaccessible to him as a normal half - ghost. He might find a hidden lair of an old enemy in the mountains while flying around in his dragon form, and then has to figure out how to defeat this enemy while still learning to control his new abilities.
One possible reason could be that he's pushed too far by the constant attacks from ghosts. Maybe he gets tired of always being the good guy and having to protect everyone all the time. It could be that he feels unappreciated and that could lead to a dark turn.
The original Danny Phantom story mainly focuses on his ghost - fighting adventures and his struggle to balance his normal life and his superhero identity. In contrast, the diaper fanfiction adds an entirely new and rather odd element. It takes the story in a direction that the original never did, focusing on situations related to the diaper which are not part of the core themes of the original.