Perhaps the male OC is an undercover agent sent to investigate something within the police department in the Blue Bloods world. He has to navigate the complex relationships and hierarchies while keeping his true identity a secret. This could lead to a lot of tense and exciting moments as he tries not to blow his cover.
The OC could be a medical professional who treats Linda's family. Through this, Linda and the OC get to know each other. They start to rely on each other's expertise - Linda for her knowledge of the police world, and the OC for medical advice. This relationship could develop into a strong friendship or more as the story progresses.
Well, perhaps there's a cursed object in the evidence room of the Blue Bloods precinct. The Winchesters hear about it through their hunter network and come to investigate. Along the way, they start to bond with the Reagan family members. Danny Reagan could be initially skeptical of the Winchesters' methods but gradually come to respect their skills in dealing with the supernatural. They could all work together to break the curse on the object before it causes more harm.
One idea could be to focus on Frank's backstory before he became the Police Commissioner. Explore his early days in the police force, the challenges he faced, and the relationships he built. This can add depth to his character in the fanfic.
There might be a fanfiction where one of the Reagan siblings decides to take a different career path for a while, like going undercover in a completely different field, and how that affects the family dynamics. It could show their growth as an individual while still maintaining their strong family ties.
One plot idea could be that the male OC is a new student at True Cross Academy. He's a bit of an outcast because of his mysterious past. As he tries to fit in, he discovers a hidden plot within the academy that involves demons. Another idea is that he has a special power that the exorcist order wants to use for their own purposes, but he has to decide whether to cooperate or not. A third plot could be that he is on a quest to find a lost artifact that has the power to either destroy all demons or give them ultimate power, and he has to face many challenges along the way.
It's special because it allows fans to put their own creative spin on the Blue Bloods world. With an OC in the mix, the possibilities are endless. You can create unique dynamics between Erin and the OC. Maybe the OC is a rival at first, but then they become friends or more. It adds depth and variety to the existing story.
One great Erin OC fanfiction is 'A New Beginning for Erin'. It delves into the character of Erin with a new original character added to the mix. The OC brings out different aspects of Erin's personality as they work together on cases. It's a really interesting read that gives a fresh perspective on Erin's story within the Blue Bloods universe.
To write a great Blue Bloods OC Fanfiction, you need to be consistent with the show's canon. Don't go against the established facts about the characters and the story world. Your OC should fit into this world organically. Also, focus on character development. Let your OC grow and change throughout the story. And don't forget about the dialogue. Make it sound natural, like how the characters in Blue Bloods talk. For instance, if you're writing a scene with the Reagan family, capture their family dynamic through the dialogue.
One idea could be that the OC is a new recruit and Washington has to train them. This leads to a lot of comical moments as the OC is clumsy at first but gradually improves. Another plot could be that the OC has a special ability that Washington discovers during a mission, and they have to figure out how to use it to their advantage. Maybe the OC is from a different planet and has unique powers.
Well, for Blue Exorcist OC fanfiction, you could have a plot where your OC is a hybrid of a human and a demon. This causes a lot of internal conflict as they struggle with their identity and are feared by both sides. They try to find a place where they can belong. Another plot idea is that your OC is a master of a new form of exorcism that is not recognized by the True Cross Order. They have to fight to get their method accepted while also using it to combat a new wave of powerful demons. And then there's the idea of your OC getting caught in the middle of a power struggle between different factions within the exorcist world, having to choose a side while trying to stay true to their own beliefs.