Some fanfictions focus on the process of becoming an animagus in a more detailed and creative way. For instance, a story might delve into the ancient spells and potions required, and how a young wizard or witch struggles to gather the rare ingredients and master the complex incantations, all while their animagus form starts to emerge in unexpected ways, like having dreams where they are in their animal form before they can actually transform.
One great one could be about a character's journey to discover their animagus form in a unique way. For example, a story where Hermione discovers she has an unexpected animagus form and how she copes with it while dealing with her studies and friendships at Hogwarts.
One interesting story could be about a character who discovers they are a snake animagus and has to hide it from their friends at Hogwarts. They might struggle with the duality of their human and snake forms, and how it affects their relationships.
One interesting fanfiction could be about the stag animagus' adventures in the Forbidden Forest. It might explore how it interacts with the magical creatures there. Another could focus on the transformation process of becoming a stag animagus, delving into the difficulties and magic involved.
There might be a fanfiction where a cat Animagus is actually a long - lost relative of one of the main characters. They initially don't realize it, but as the story unfolds, the connection is discovered through the cat's unique behaviors and abilities. For example, the cat might be able to understand Parseltongue and it's this strange ability that leads to the revelation.
One common theme could be the exploration of power dynamics. Given that Voldemort is a very powerful dark wizard and Harry has his own unique powers as an Animagus. Another theme might be the idea of redemption or change, where Voldemort is somehow changed by his relationship with Harry. However, it should be noted that these fanfictions are often very different from the original canon.
I'm sorry, but I can't really recommend specific fanfiction for this rather unusual pairing. Fanfiction can vary greatly in quality and content, and the idea of Harry Potter and Voldemort in such a relationship goes against the general themes of the original series. However, you can try searching on popular fanfiction websites like Archive of Our Own and use the relevant tags to find something if you're interested.
One interesting aspect could be seeing Harry's new form as an Animagus. Maybe he turns into a unique animal that gives him different abilities and perspectives in the wizarding world.
One interesting plotline could be Harry discovering his animagus form earlier than in the original series and using it to secretly explore Hogwarts at night. He might find hidden passages or secrets that were previously unknown.
There are those that focus on how Muggles might react if they were suddenly exposed to magic. For example, a story where a Muggle discovers a magical artifact and has to navigate the strange world of magic with the help of a friendly witch or wizard. In these fanfictions, the interactions between Muggles and wizards are really fascinating.
There might be a fanfiction where a group of friends get matching Harry Potter slash tattoos. For example, one has a tattoo of Harry's glasses crossed with a lightning bolt, and another has Hermione's book and a wand. The story could revolve around how these tattoos bring them closer together and the adventures they have because of it. It could show how they use the symbolism of the tattoos to solve mysteries or face challenges in the wizarding world.
One interesting story could be about Harry Potter and a Hippogriff. Maybe it's a story where Harry forms an even deeper bond with a Hippogriff than he did in the original series. He could be learning more about their kind and having adventures together in the Forbidden Forest.