Obviously, Harry Potter would be one of the main characters. And the snake, which plays a crucial role as per the title. There might also be other characters from the original series like Hermione and Ron, who could interact with Harry in the context of his new relationship with the snake.
Well, in this fanfiction, perhaps the snake is a magical guide for Harry. It could lead him to hidden places in Hogwarts. For example, it might show him secret passages that were previously unknown, adding an exciting new dimension to the story. This could also change the dynamics of his relationships with other characters, as he now has this special connection with the snake.
Dear [Character Name], This letter of thanks is long overdue. You've been an amazing part of my Hogwarts journey. Whether it was in Potions class, where you helped me avoid blowing up my cauldron, or on the Quidditch pitch, cheering me on from the stands. Your kindness and selflessness have not gone unnoticed. I've learned so much from you, from how to handle a difficult Boggart to how to find the beauty in the simplest of magic spells. You are truly a gem in the wizarding world, and I am so lucky to have you in my life. Thank you with all my heart. [Your Name]
It could also be a snake from the Forbidden Forest. There are many unknown and mysterious creatures in there. A snake from that forest might be more in tune with the natural magic of Hogwarts. Harry, being the curious and kind - hearted person he is, might come across it during one of his adventures in the forest and start a friendship with it.
It could be Nagini. Even though in the original series she was more of a servant to Voldemort, in the fanfiction, she could have a different personality and form a bond with Harry.
Maybe it's an anonymous gift from someone who has been observing Harry. This person could be a former student of Hogwarts who has a special connection to snakes and sees that Harry has a kind heart and would take good care of the snake. So they leave the snake for Harry to find with a simple note that just says 'For Harry Potter'.
The snake's help could represent an unexpected alliance. In the Harry Potter series, snakes are often seen as symbols of Slytherin, which is usually at odds with Harry. So it's significant as it breaks the stereotype of enmity between Gryffindor (represented by Harry) and Slytherin.
The snake might use its ability to move stealthily. It could spy on the enemies for Harry Potter. For example, it can slither into hidden places where humans can't easily reach and gather important information.
Snake magic in Harry Potter fanfiction can be used to show a character's dark side. Since snakes are often associated with Slytherin and dark magic in the original series, in fanfiction, a character using snake magic might be on a path towards the dark arts. For example, they could use snake magic to control others or gain power in a more underhanded way.
Well, in some fanfictions, he might find it in the Forbidden Forest during one of his adventures. Maybe it was injured and he felt a connection to it, so he decided to take it as a pet.