One possible plotline could be Harry adjusting to a new family that actually loves and supports him. He might discover new magical abilities or a different side of the wizarding world. Another could be his relationship with his adoptive family as they learn about his past and the challenges he faced at the Dursleys.
Well, in some fan fictions of this type, Harry could be adopted by a powerful magical family from the Dursleys. This new family might train him in advanced magic that he didn't learn at Hogwarts. Or perhaps they help him uncover secrets about his parents that were hidden from him all this time. It could also involve Harry having to deal with the jealousy or envy of other wizards who don't like his newfound status in this adopted family.
Obviously, Harry Potter himself is a central character. There could be his adoptive parents. They might be kind-hearted wizards or witches who take Harry in. And perhaps his new siblings, if there are any in the adopted family. There could also be some of his friends from Hogwarts who interact with him in this new situation.
In some fan fictions, Severus might save Harry from the Dursleys because he realizes that Harry is the key to defeating Voldemort in the long run. He might see that the Dursleys' treatment is making Harry weak and less likely to be able to face Voldemort. So, he intervenes, maybe by intimidating the Dursleys into treating Harry better and providing him with proper education about the wizarding world. He could also give Harry some potions to boost his health and magical abilities that have been stunted by the Dursleys' neglect.
One possible plotline could be Reid's journey in discovering his birth family while still maintaining a strong bond with his adoptive family. It might involve him uncovering secrets about his past that change his perspective on life.
One possible plotline could be that a new character, perhaps a powerful witch or wizard, arrives at the Dursleys' place and whisks Harry away to a magical hideaway. There, Harry meets a love interest who has also been in hiding from the dark forces. They bond over their shared experiences and start to fall in love.
Perhaps in the fanfic, a time - traveling wizard goes back to save Harry from the Dursleys. This would lead to a lot of changes in the timeline. Harry might be introduced to magic much earlier and form different relationships. He could also have a different understanding of his parents' history and his own role in the wizarding world as a result of being removed from the Dursleys' environment.
There's not enough information to know who the 'harrys' are. It could be a name unique to a particular story or community.
One interesting plotline could be Harry showing early signs of magic that the Dursleys try to suppress. For example, he might accidentally make Dudley's toys float when he's angry or frustrated.
One possible plotline could be Harry finding a new family among the magical creatures. For example, he might be taken in by a friendly centaur herd who teach him their ways of magic and survival. Another could be Harry being found by a secret group of wizards who are against the Dursleys' cruel treatment and they help him develop his magic in a more positive and nurturing environment. And there could also be a plot where Harry discovers a hidden magical power within himself as a result of the abandonment, like the ability to communicate with the spirits of Hogwarts, which then guides him on a new path to face Voldemort.
One possible plotline could be that the Dursleys start to show their love by secretly protecting Harry from the wizarding world's threats. Maybe they learn about a dark wizard targeting Harry and use their Muggle ways to keep him safe without him even realizing it.
Well, in some fanfictions, Harry might control the Dursleys by making them understand the wizarding world. He could show them magical things and, as a result, they start to respect him and his abilities. This could lead to a whole new dynamic in the household, where the Dursleys are no longer mean but rather in awe of Harry and his magic.