In many fanfics, it's related to a powerful dark magic threat. Harry might sacrifice himself to protect Hermione from a dark spell or a powerful enemy. For example, he could jump in front of a killing curse meant for Hermione. His sacrifice is usually seen as an ultimate act of love and friendship, and it often has a big impact on the wizarding world in the fanfic. It might inspire others to be more selfless or it could change the balance of power between good and evil.
Some fanfics show that Harry's sacrifice for Hermione is also a way to atone for past mistakes or to fulfill a prophecy. He might see it as his destiny to protect her at all costs. And when he sacrifices himself, it can lead to a series of events that reshape the story. For instance, Hermione could be empowered by his sacrifice and go on to defeat the ultimate evil in the fanfic world. His sacrifice becomes a catalyst for change in the overall plot.
One popular fanfic could be 'The Ultimate Sacrifice'. In it, Harry's self - sacrifice is a very emotional and heroic act. He does it out of deep love and friendship for Hermione.
One way it could happen is if there's a dark force that is specifically targeting Kurma to gain ultimate power. Naruto, being the selfless hero he is, steps in. He might use some sort of forbidden jutsu that binds his life to Kurma's safety. As he sacrifices himself, his body could turn into pure energy that surrounds and shields Kurma. This would leave the ninja world in shock. People would remember Naruto as a true hero, and Kurma would be left with a new sense of purpose, perhaps to carry on Naruto's will and protect the world in his stead.
In some fanfictions, the life debt claim can lead to a power imbalance in their relationship at first. However, as the story progresses, they work together to overcome this. It might also lead to unique magical bonds or abilities being formed between them. For instance, they could share a special form of magic that only those with a life debt connection can access. This then leads to new adventures and challenges as they explore these new powers.
Often, atonement in Harry Potter fanfiction involves characters making up for past mistakes. For instance, a Death Eater might try to atone by saving the lives of the good guys. It's about redemption and changing one's ways.
Indifference in Harry Potter fanfiction can create really unique storylines. For example, if Ron is indifferent to his family's expectations of him. Usually he's in the shadow of his brothers, but in this case, he could pursue his own interests, like maybe he becomes more interested in Muggle technology instead of pure wizarding things. This would lead to him having a different role in the group, and might even cause some conflicts as his friends try to understand his new direction.
In 'Harry raises self' fanfics, it usually starts with Harry being in a situation where he has to fend for himself. This might be due to the lack of proper guidance from adults. For example, he could be abandoned in a strange place. This forces him to learn survival skills, which in turn develops his character.
Often, it creates a situation where they have to rely on each other. For example, in some fanfics, the accident might give them shared magical symptoms that only they can understand and solve together.
Often, it starts with a wild party or celebration where too much butterbeer or some other wizarding drink has been consumed. Characters make hasty decisions and end up in a marriage situation. Then there's confusion and chaos as they realize what they've done.
In Harry Potter fanfiction, the 'daddy sucks' idea might be expressed through the emotional turmoil of a character. For example, Neville Longbottom could be shown as having a difficult time dealing with the memory or the reality of his father who is in St. Mungo's. The fanfiction could focus on how Neville feels let down by his father's absence in his life and how that shapes his character in a different way from the books.
It could play out by dictating the relationships between characters. For example, two characters who are fated to be friends or enemies might be drawn together or pushed apart by these'strings'.