There may well be. The world of fanfiction is incredibly diverse, and fans often like to blend different elements from various sources. Given that Harry Potter has a large and passionate fan base, and the idea of introducing a unique virus like the Blacklight virus into the magical world could make for an interesting story. But finding it might require some dedicated searching on different fanfiction repositories, and also checking relevant tags and categories related to both Harry Potter and viruses.
It could be about how the Blacklight virus enters the wizarding world. Maybe a Muggle - born student unknowingly brings it into Hogwarts. Then, the virus starts to affect the magic of the wizards, causing chaos as spells go wrong. Harry Potter might be the one to figure out how to stop it, using both his knowledge of magic and some newfound understanding of this strange Muggle virus.
The 'harry potter blacklight virus fanfiction' could be a very creative and unique take on the Harry Potter world. It might involve the virus being related to dark magic or a forgotten aspect of wizarding history. For example, it could have been created by a long - forgotten dark wizard and now resurfaces, threatening Hogwarts and the entire wizarding world. The characters would then have to use their knowledge of magic, both traditional and unorthodox, to deal with this new threat.
Obviously, Percy is one of the main characters since it's in the title. He's the one who has the Blacklight virus. His friends from his original story, like Annabeth, could also be main characters. They might be involved in trying to help Percy deal with the virus, or they could be in danger because of Percy's condition.
Harry might become more of an outcast. His friends may not understand what's happening to him with the virus. This could make him bitter at first, but as he learns to control the virus, he could become more self - reliant and determined. He would also have new powers from the virus, which could make him a bit cocky at times as he figures out how to use them.
Since it's fanfiction, there could be new characters created specifically for this story. Maybe a healer who has a special knowledge of the blacklight virus and its effects on magic. Or perhaps a character who is somehow immune to the virus and becomes crucial in the fight against it.
One possible plotline could be Percy's struggle to control the virus. He might initially be terrified of the changes it brings to his body and abilities. For example, he could find himself with enhanced strength but also a growing hunger that's hard to satisfy in a normal way. Another plotline could involve Percy trying to hide his condition from his friends, fearing their reactions. He may worry that they'll see him as a monster or be in danger just by being around him.
In a fanfiction, Harry having the Blacklight virus could lead to a situation where he teams up with some magical creatures. The virus gives him unique abilities that help him communicate with and understand these creatures in ways others can't.
I recommend the following novels related to the Blacklight Virus to you: "Spirit Cage's Traversing the Heavens","Invincible From the Beginning","Endless Surpasser","Blacklight Virus: Invasion of the Multiverse, The Heavens from the Blacklight Virus, Infinite Devour of the Heavens, The Ark of Tomorrow's Integration Fire, The Undying from the Prototype of Murder, The Bio-Maniac in the Marvel World, Doomsday Virus Body, The Blacklight Virus Creator in Resident Evil, Virus Monarch: The Unlimited Evolution of Cell Mutation at the Beginning, The Fusion of Black Light at the Beginning of Doomsday. I hope you like my recommendation. Muah ~
Some fanfictions might focus on the moral implications of the blacklight virus. Characters could struggle with whether to use the virus - if they find a way to control it - for good or for evil. There could also be stories about survivors trying to find a cure, facing various challenges and making difficult choices along the way, like sacrificing one person to save many or dealing with the distrust among the group.