A handyman character who is always there to offer advice and practical help to the OC. He could be a gruff but kind - hearted man with years of experience in home improvement.
The nosy neighbor can be a popular character. They might constantly peek over the fence, give unwanted opinions on the OC's home improvement projects, and sometimes even get involved in a comical way.
Maybe an OC with a passion for sustainable living decides to turn their entire home into an eco - friendly space in the home improvement oc fanfiction. They could install solar panels, create a rainwater collection system, and upcycle old furniture, all while facing opposition from skeptical neighbors.
Captain Cold could be an interesting addition. He might see the OC as a new target or an opportunity. Maybe the OC has something that he wants, like a valuable piece of technology. Or, he could form an unlikely alliance with the OC against a greater threat. Another character would be Killer Frost. If the OC has heat - based powers, they could have an epic battle or a complex relationship with Killer Frost. And of course, Harrison Wells, in any of his incarnations, could play a significant role. He might be mentoring the OC or using them for his own secret plans.
Hermione Granger is a great character to include. Her intelligence and love for knowledge can interact in interesting ways with an SI or OC. Harry Potter himself, of course, as he is the central figure in the original series. And Draco Malfoy, his complex personality and family background can create a lot of drama when paired with an SI or OC. For example, an SI who tries to befriend Draco and change his views towards Muggle - borns.
A powerful Raikage - like character as an OC would be great. This character could be extremely strong in physical combat and have a no - nonsense attitude towards protecting Kumogakure.
Terra could be a great addition. He could act as a sort of mentor or a source of conflict. For example, Terra might be initially suspicious of the OC's intentions towards Ventus. Or he could be the one to encourage Ventus to pursue his feelings for the OC, seeing how happy the OC makes Ventus.
You could include a passionate and talented lead dancer like Mia from 'Step Up' - type character. Also, a strict but fair dance instructor who has high expectations for their students. And don't forget about the rival dancer who is always trying to outshine the main character.
A court jester can add some humor. He can be the one who sees through the courtly pretenses and gives the emperor some down - to - earth advice in a comical way.
One popular character could be an OC who is a rebel. They don't conform to the strict rules and traditions of the heir society. They are constantly challenging the status quo and inspiring others to do the same. This kind of character often stands out and becomes a fan favorite.
One popular Hawkeye OC is 'Aria'. In many fanfictions, she is depicted as a skilled archer herself, trained in a different style than Hawkeye. She often teams up with him to take on various threats. Another is 'Max', a tech - savvy OC who provides Hawkeye with high - tech gadgets and intel for his missions. And then there's 'Luna', an OC with a mysterious past and the ability to sense danger before it arrives, which helps Hawkeye stay one step ahead in dangerous situations.
One popular type of OC is a female pirate who is as strong - willed as Katakuri. She challenges him in a battle of wits and strength, and their interactions create a lot of tension and intrigue in the fanfiction. For example, she might try to steal a precious treasure that Katakuri is guarding.