Perhaps Ron has made a new, strange friend who he doesn't want Harry or others to meet yet. He's keeping people away to give this friendship a chance to develop without interference. When Harry catches him, Ron might be defensive at first. However, after some discussion, he could introduce his new friend to Harry, and it turns out to be an interesting addition to their group.
One possibility is that Ron has a secret he wants to protect and he thinks keeping others away is the best way. Maybe he's found a magical object that he doesn't want others to misuse. When Harry catches him, it could lead to a big argument between them at first. But then, they realize they need to work together to handle the situation properly.
It could be that Ron is feeling insecure about something in his life, like his Quidditch skills. He doesn't want others to see him struggle, so he keeps them away. When Harry catches him, Harry might be understanding and offer to help Ron improve. This could strengthen their friendship as they work through Ron's insecurities together.
Their relationship could become strained initially. Harry might feel betrayed or confused as to why Ron is acting this way. Ron, on the other hand, could be angry that Harry has caught him. But if they communicate openly, it could lead to a deeper understanding between them.
Well, it could be about them running away to avoid some dark magic threat at Hogwarts. Maybe a new dark wizard has emerged and they don't trust the school's ability to protect them at that moment.
Maybe they run away because they are tired of the constant danger at Hogwarts. They've faced so many threats, and they just want a break. So they run to a peaceful place where no one knows them.
One possible plot could be that they have a major disagreement over a Quidditch match. Maybe Ron blames Harry for losing the match because Harry made a risky move that didn't pay off. This causes a rift between them, and they start to see each other as rivals rather than friends. They compete in everything from academics to getting the attention of a certain teacher.
He could be walking away from his friends after a big fight. Perhaps there was a misunderstanding about his role in the fight against Voldemort. For example, his friends might think he took unnecessary risks, and Harry, feeling unappreciated, decides to leave and figure things out on his own. He might go to some far - off place like the Forbidden Forest to be alone and think about his future.
Well, it could be that Harry moves away to escape some dark magic threats in his hometown. Maybe he goes to a far - off magical community where he has to learn new spells and make new friends.
One possible plot could be that Harry discovers a way to control the Basilisk instead of killing it. Maybe he uses some ancient magic or a special spell. He might keep it hidden in the Chamber of Secrets and use it to protect Hogwarts from other dark forces. For example, when Voldemort sends his Death Eaters, the Basilisk could be a secret weapon that Harry unleashes to fight them off.
It could be that Ron and Hermione abandon Harry due to a prophecy that they misinterpret. They believe that by being with Harry, they will bring doom to the wizarding world. So they go into hiding. Harry, on the other hand, is determined to change the course of the prophecy. He embarks on a journey to find the truth behind it, all while feeling the pain of his friends' desertion. He has to fight against dark forces that are taking advantage of the situation.
In such a fanfiction, it might be that Harry and Ron are influenced by a powerful dark spell. This spell makes them see Hermione as a threat, so they abandon her. Hermione then has to find a way to break the spell's influence on them while also dealing with the loneliness and danger she's now in. She could seek help from other Hogwarts students or even some friendly magical creatures.
Maybe Ash discovers Yveltal in a damaged state due to some evil team's actions. He decides to help it and in the process, forms a bond with Yveltal. Eventually, Yveltal allows Ash to catch it.