One idea could be a story where a prefect discovers a hidden magical object in the prefect bathroom. For example, a magical key that unlocks a secret chamber within the bathroom that has been forgotten for centuries. Another could be about different house prefects coming together in the bathroom to solve a mystery that is somehow related to the Hogwarts plumbing system but has deeper magical implications. Maybe there's a spell gone wrong that's causing strange things to happen in the bathrooms and they need to figure it out before it affects the whole school.
A possible plot could be that the prefect bathroom becomes a place of refuge for a prefect who is being bullied. They start to decorate the bathroom in a way that makes it their own safe haven. As they do this, they discover that the bathroom has the power to transform into different magical landscapes depending on the mood of the person using it. This discovery leads to a series of adventures as the prefect invites their closest friends to experience the magic of the bathroom too.
Perhaps a fanfic where a new prefect is extremely nervous about using the prefect bathroom for the first time. They enter and find that there are strange, friendly ghosts that inhabit the bathroom only when a prefect is present. These ghosts start to tell the new prefect tales of Hogwarts' past and secrets that are related to the prefects over the years. The prefect then uses this new - found knowledge to help a fellow student in trouble.
A great plot could be a prefect who discovers a hidden passage in the castle that leads to an old, forgotten part of Hogwarts. This prefect then has to decide whether to keep it a secret or share it with the school authorities. Also, a story about a prefect who has to mediate between two feuding groups of students within their own house. It could show the challenges of leadership and the importance of unity within the house.
You can develop characters by having them face challenges unique to the prefect bathroom setting. For instance, a prefect who has a fear of water but has to deal with the large pool in the bathroom. As they try to overcome this fear, we see their determination and growth. Also, characters can be developed through their interactions with the magical elements of the bathroom. If a character is curious and starts to explore the hidden corners and discovers a magic mirror that shows their deepest desires, they might change their goals and priorities based on what they see, which would be a great way of showing character development.
Well, there are several factors. Firstly, if it gives a new perspective on Hogwarts life. Since prefects have a certain level of authority, seeing how they interact with teachers and students differently can be fascinating. Secondly, character development. If the fanfic focuses on a prefect's growth, like from being a rule - follower to a more independent thinker. Also, mystery and intrigue. Maybe there's a secret that only the prefects are aware of, or they are involved in solving a mystery that affects the whole school. All these elements combined can make a Prefect Harry Potter fanfic really interesting.
A plot could be that the bathroom at Hogwarts has become a portal to another dimension, but only Harry can sense it. Every time he enters the bathroom, he gets glimpses of this other world. He has to figure out why this is happening and if there is any danger associated with it. He might start to keep a journal of his experiences in the bathroom, trying to piece together the mystery.
Well, you could have a fanfic where Voldemort uses DND - style dark magic to open portals to other dimensions. The Order of the Phoenix has to quickly learn DND - style combat and magic rules to fight off the new threats that come through these portals. Harry could be sent on a special mission to find a DND - style mage who can teach them the counter - spells. Meanwhile, the Death Eaters are also trying to master this new form of magic for their own evil purposes. This would create a really exciting and unique story.
Perhaps a plot where the protagonist can choose to either side with the Ministry of Magic during a time of political unrest within the wizarding world or join a rebel group. This would involve different magical battles and moral dilemmas depending on the choice. In the 'harry potter cyoa fanfic', this could show different aspects of the wizarding society that we don't often see in the original books.
A cool plot for a Harry Potter Twilight fanfic could be a competition. The wizards from Harry Potter and the vampires and werewolves from Twilight compete in a series of challenges. These challenges could test both magic and the unique abilities of the Twilight characters. Or perhaps a love triangle between a Harry Potter character, a Twilight vampire, and a Twilight werewolf. It would be interesting to see how the different cultures and powers interact in matters of the heart.
Another plot could focus on the lives of the secondary characters from the original series. For example, Neville could be the head of Herbology at Hogwarts and discovers a new, dangerous plant that has some sort of connection to an ancient magic. The 'carry on fanfic' could then be about how he and his students deal with it, with some cameos from the main characters.
One idea could be that a dragon escapes from Gringotts and Harry has to use his skills to track it down. Maybe the dragon has a special connection to a powerful dark magic item that Voldemort was after.
One idea could be that Voldemort somehow enters the Runescape world to seek more power. Harry and his friends follow him there to stop him. They have to learn the rules of Runescape quickly to be able to fight Voldemort. Another idea is that a Runescape wizard discovers a portal to the Harry Potter world and brings some of the unique items from Runescape, like special runes, which causes a stir in the wizarding world.