There's also a possibility that it's a character we already know from the original Harry Potter series, like Hermione. She already loves learning and is good at most subjects. It would be interesting to see her delve deeper into arithmancy and become a true arithmancy master, using her skills to help Harry in new and unexpected ways.
Maybe it's an older wizard who has been studying arithmancy in secret for years. He decides to come out of the shadows and share his knowledge at Hogwarts, becoming the central figure in the story as he mentors the students and uses his skills to solve various magical problems.
A Muggle - born student could be the main character. They might not have the same preconceived notions about magical beasts as the pure - bloods and half - bloods. Their fresh perspective could lead to new ways of handling and understanding the beasts. They could be the one to discover a new breed of beast that has been hiding in plain sight, right on the outskirts of Hogwarts.
Perhaps it could be an older version of one of the main characters from the original series. For instance, an adult Harry Potter who has become a master of certain types of magic and is now on a new adventure. He could be traveling to different parts of the wizarding world to teach or to learn more advanced magic techniques. Another possibility is that it could be a character like Dumbledore in his younger days when he was on his own journey to become the great wizard he was known to be.
It could be a new student at Hogwarts who discovers their talent for runes early on. Maybe they come from a family with a long - forgotten tradition of rune - making and they are the first in generations to revive it.
Hermione could also be a great main character. Given her thirst for knowledge, she might be the one to first study and understand the concept of Haki in the fanfiction. She could then use it to her advantage in battles and also to help her friends, perhaps even using Haki - enhanced magic to break through difficult spells or magical barriers.
Perhaps it could be a well - known character from the original Harry Potter series who discovers a new aspect of their magic. For example, Hermione might find that she has an aptitude for seal magic while researching some ancient texts in the library. She could then use her knowledge and newfound ability to solve some of the problems in the wizarding world.
It could be an original character created specifically for the fanfiction. Maybe a young wizard or witch who discovers their Shadow Master abilities by accident.
One interesting plot could be a character using arithmancy to predict the return of a dark force. They might discover hidden patterns in numbers related to past dark events and use that knowledge to try and prevent a new threat.
It could be an original character created specifically for this fanfiction. Maybe a young wizard or witch who has always been an outcast in the wizarding world and discovers their unique ability to connect with dark dragons.
Arithmancy can be depicted as a very academic and studious pursuit within fanfiction. Writers may show students spending hours poring over arithmancy textbooks, trying to solve difficult numerical equations related to magic. It could be used as a way to distinguish the more studious characters from the others in Hogwarts.
Arithmancy can be a tool for character development. For some characters, being good at arithmancy shows their intelligence and discipline. For instance, Hermione might be shown delving deeper into arithmancy, which further emphasizes her studious nature.