Definitely not. The Last Witch Hunter has nothing to do with DC Comics. It's an independent production with its own distinct concepts and narrative elements that are not related to DC's comic book world.
The primary character is, of course, the last witch hunter. However, we can assume there are other characters as well. There could be a young apprentice - type character who looks up to the hunter and wants to learn from him. This character could add a sense of new - blood and naivete to the story. There might also be a villainous witch who is the main antagonist, leading the forces of dark magic against the hunter. And then there could be some ordinary people in the story who are affected by the conflict between the hunter and the witches, showing the impact of this battle on the world at large.
One prevalent theme is redemption. Many OCs have a past they are trying to atone for. This ties in with the moral grayness of the 'The Last Witch Hunter' world. Also, the theme of discovery is big. OCs are constantly discovering new things about the world, the magic, and the other characters. It makes for an exciting read as they navigate this unknown territory.
One great 'Harry Potter and The Last Witch Hunter' fanfiction is 'The Crossover Chronicles'. It combines the magic of Harry Potter's world with the gritty, dark elements of The Last Witch Hunter. It has an interesting plot where Harry Potter teams up with the Witch Hunter to fight a new, powerful dark force that threatens both their worlds.
One possible plot could be an OC who is a young witch hidden in the human world. She discovers that she has a special power that could either save or destroy the balance between witches and humans. The OC crosses paths with the last witch hunter and at first, they are enemies. But as they face a common, greater evil like an ancient, dark magic that threatens to consume both their worlds, they must learn to work together. This could involve the OC teaching the witch hunter about the more nuanced aspects of witchcraft, and the hunter protecting the OC from those who would harm her for being a witch.
One of the most creative crossovers is the idea of a magical school in the world of The Last Witch Hunter, inspired by Hogwarts. In this fanfic, Witch Hunters' children start to attend this school, and they learn both traditional Witch Hunter skills and magic from the Harry Potter universe. It's a great mix of the two worlds' educational systems and magic concepts, and it shows how the two different cultures can blend together.
One great 'The Last Witch Hunter' OC fanfic is 'The Lost Witch'. It has an interesting original character who teams up with the main protagonist. The story is full of action and mystery.
First, consider their backstory. For example, if they are a witch, think about how they came to learn magic. Were they born into a coven? Or did they discover their powers on their own? Also, give them a unique power or ability that fits within the world of 'The Last Witch Hunter'. It could be something like the ability to control shadows, which would be useful in a world full of danger. Their appearance can also play a role. Maybe they have a distinct mark on their body that is related to their power. And don't forget about their personality. If they are a good witch, they might be kind - hearted but also have a feisty side to protect themselves.
Perhaps a new type of creature that is neither from the Harry Potter world nor the Witch Hunter's world. It could be a result of some dark magic experiment gone wrong. This creature could have the ability to nullify magic in some ways, which would be a huge threat to both Harry and the Witch Hunter.