Well, an 'Evil Morty' fanfic in the 'Rick and Morty' universe can be really interesting. Evil Morty is such a complex character. In these fanfics, he could be explored further in terms of his motives. Maybe he's tired of being in Rick's shadow or he has some grand plan to take over the multiverse that wasn't fully shown in the show. Fanfics give the writers the freedom to expand on his backstory and what makes him tick.
Well, in theory, it could. Fanfics often like to blend different fictional universes. However, in the official Harry Potter lore, there are no lightsabers. But in a fanfic, an author could come up with some creative magic or a cross - universe event that brings lightsabers into the wizarding world. Maybe a powerful wizard discovers a way to create a weapon similar to a lightsaber using magic and some rare materials.
In such a fanfic, one aspect could be how Jessica views Morty. She might initially be dismissive or not even notice him, but as the story progresses, she could start to see his hidden qualities. Also, the fanfic could play with the different dimensions in Rick and Morty. For example, there could be a dimension where Morty and Jessica are already a couple, and Morty from our main dimension tries to learn from that version of himself to win Jessica in his own world.
He could find it during one of his missions. Maybe he's exploring an ancient ruin and stumbles upon the lightsaber. It could be in a chest or just lying there, and Naruto, being curious, picks it up.
Pikachu would probably be very curious. It might zap the lightsaber a bit to see what would happen, and then be in awe of the bright blade. It could also get a bit protective of Ash when he wields the lightsaber, as if it senses the added danger.
Perhaps it's given to him by a mysterious figure. This figure could be from another dimension or a very old ninja who has been in hiding for a long time. They recognize Naruto's potential and power, and decide that he is the one worthy of wielding the black lightsaber. This could be part of a bigger plan to help Naruto defeat a new and powerful enemy that neither the ninja world nor the normal means of combat can handle.
One great female Morty fanfiction could be one where she goes on an adventure by herself, exploring a new dimension filled with strange creatures. It shows her as a strong and independent character, breaking away from the usual Morty and Rick dynamic.
Well, in the world of fanfiction, people can take characters in all sorts of directions. But in the context of 'Rick and Morty', the idea of Rick abusing Morty in the fanfiction is a deviation from the show. The show focuses on their interdependent relationship, with Rick being the brilliant but flawed mentor and Morty being the somewhat naive sidekick. Fanfiction writers might create such scenarios to explore the darker side of their relationship, but it's not a part of the main narrative.