sakura loses her arm

One possible reason could be extreme emotional distress. Maybe she feels like she has failed Sasuke in some way, like not being able to save him from the darkness, and she self - harms as a form of punishment. Another reason could be in a situation where she has to make a sacrifice. For example, if Sasuke is in danger and her cutting off her arm is the only way to activate a certain power or jutsu to save him.

Maybe he starts to train with one - armed techniques. He could learn from other one - armed ninjas if there are any in the fanfiction world. His friends would also play a big role. They might encourage him to keep going or help him in his training.

Her friends would be extremely worried and would do everything they can to support her. They might feel guilty if they think they could have prevented her memory loss. Her family, if there are any in the story, would be heartbroken and try to take care of her like she was a child again.

It could be that she loses her license due to a mistake during a mission. Say she fails to protect an important artifact or person. As a result, she's stripped of her license. To get it back, she may have to train harder than ever, learn from her mistakes, and perhaps seek help from her friends and mentors. She'll need to show that she's now more reliable and capable to be a ninja again.

Often, in Sakura - loses - her - memory fanfiction, she might mistake her enemies for friends or vice versa due to the memory loss. This can lead to some really interesting situations. For example, if there was an antagonist who was pretending to be a friend, she might unknowingly help them in their evil plans at first. Then, as the story progresses, she slowly starts to piece things together.

Well, without having read the 'harry loses crystal arm fanfic', it's hard to say precisely. But it might involve a story where Harry has this unique crystal arm, perhaps it was a gift or the result of some kind of experiment. Losing it could be a central event that sets off a chain of other events. It could lead to him on a quest to get it back, or it could make him face some inner demons as he has to adjust to life without this special part of himself.

It could be a rogue ninja who has a grudge against Sakura. This ninja might set her up in a way that makes her lose her license.

It could be a new and powerful rogue ninja who manages to overpower Naruto and cause him to lose his arm. Maybe this antagonist has some sort of vendetta against Naruto or the Hidden Leaf village.

Well, in some 'naruto loses arm fanfiction', it might be a result of a forbidden jutsu gone wrong. Naruto might be exploring a new and dangerous form of power, and the price is his arm. This would then set off a chain of events where he has to find a way to either get his arm back or adapt. He could also face discrimination from some in the ninja community who see him as weakened, but he'd prove them wrong by his unwavering spirit.

One possible plot could be Naruto losing his arm during a battle with a powerful new enemy. He then has to struggle with not only the physical loss but also the emotional and mental toll it takes on him as a ninja. He might have to learn new fighting techniques that don't rely on two arms.