Well, he could discover new magical abilities or knowledge. Since Hogwarts has a vast curriculum, when Harry gets serious, he may delve deeper into subjects like Ancient Runes or Arithmancy, unlocking secrets that were previously overlooked. This could also lead to him making new friends who share his new - found academic interests. For example, he might become closer to Hermione in a different way, as they study more advanced topics together. He could also start to influence his classmates to take school more seriously as well, creating a positive academic environment in Gryffindor.
I don't have the exact timing of Gojo's death in the manga at hand. But usually, you can find such crucial plot points by closely following the story's progression or referring to fan communities and discussions dedicated to the manga.
He becomes more responsible. Instead of getting into as many impulsive adventures, he focuses on his studies and the duties that come with being a student at Hogwarts.
The change in Naruto's character. Usually, he's the go - lucky and sometimes clumsy ninja. But in these fanfics, when he gets serious, it's like seeing a whole new side of him. It makes the story more exciting as he approaches problems in a different way.
A third theme could be facing greater challenges. In these fanfictions, the challenges are so big that Luffy can't just rely on his normal, laid - back self. He has to be more serious to overcome them.
One great 'Harry gets serious' fanfiction is 'The Serious Side of Harry' on FanFiction.net. It shows Harry dealing with the weight of the prophecy in a very mature way.
A third theme could be self - discovery. As Natsu gets serious, he may also discover new aspects of himself. Maybe he realizes he has more power within him than he thought, or he discovers a different way of thinking about his role as a dragon slayer. This can lead to some interesting character arcs in the fanfiction.
It starts at a specific point in the manga, but I can't recall exactly without looking it up. You might want to check some manga forums or dedicated fan sites for the precise chapter.
Well, 'Serious Naruto: A New Era' is another good one. In it, Naruto is dealing with the aftermath of a great war and has to be serious in rebuilding the village. The story shows how he overcomes various challenges and grows not just as a ninja, but as a person. It also has some great action scenes that highlight his new - found seriousness.