The baby could be the child of a fallen ninja. Maybe the ninja was an ally of Naruto's and before dying, entrusted Naruto with the baby. This would add an emotional depth to the story as Naruto would feel a great sense of responsibility to raise the baby well.
The baby might be a victim of some sort of experiment. Naruto finds the baby in a secret laboratory and decides to adopt it. As the baby grows, it could have some unique abilities or problems due to the experiment, and Naruto has to help the baby overcome these challenges.
It could be a baby with a mysterious origin. For example, it might be a descendant of an ancient clan that was thought to be extinct. Naruto, being curious and having a big heart, adopts the baby to figure out its past and give it a better future.
Well, in such a fanfic, the plot might involve Naruto finding a baby in a difficult situation, like maybe the baby was orphaned after a battle. Naruto, being the kind - hearted hero he is, decides to take the baby in. He'd then have to learn how to take care of a baby while still handling his ninja duties. He might ask his friends like Sakura for advice on baby - care, and the story could also show how the baby grows up influenced by Naruto's values and the ninja world around it.
Well, one possible plot could be that Naruto discovers an orphaned baby during one of his missions. He decides to take the baby in because he understands what it's like to grow up without parents. He then has to learn how to take care of a baby while still being a ninja. Maybe he gets help from his friends like Sakura who gives him medical advice for the baby's health, and Kakashi who gives him some wisdom on raising a child.
Some of the more traditional ninja elders might oppose Naruto's decision. They could think that Naruto, as a busy ninja, doesn't have the time to take proper care of a baby. They might be worried that it could affect his performance in important missions.
The Ministry of Magic itself could be an antagonist. If they don't approve of Hermione's adoption due to her age or some bureaucratic reasons, they could try to take the baby away. They might think she's not fit to raise a child, which would create a lot of conflict in the story.
Maybe some dark elves or other villains from the Marvel universe. They could see the baby as a valuable asset or a threat, and try to harm the baby or use it against Loki. Since Loki is now responsible for the baby, he has to fend off these threats to keep the baby safe. For instance, the dark elves might think the baby has some special power and they want to harness it for their own evil purposes.
Well, it could be that Itachi sees the potential in baby Naruto and decides to protect him from the dark forces in the ninja world. Maybe Itachi wants to raise Naruto to be a powerful and kind - hearted ninja, away from the hatred that plagues their village.
One possible plot could be that Kurenai, seeing Naruto as a lonely and neglected baby, decides to take him in. She could then start teaching him basic ninja skills from a very young age. Naruto would grow up with a mother - like figure in Kurenai, which would change his personality in some ways. He might be more confident and less of a prankster as he has the love and support he needs early on.
The story could also focus on how Kakashi's decision to adopt Naruto affects the village's perception of Naruto. People might start to see Naruto in a different light, not just as the Jinchuriki but as Kakashi's son. This could lead to Naruto having a more positive experience growing up in the village, with less ostracism. Kakashi would have to navigate the politics of the village while also raising Naruto, which could add a lot of interesting twists to the plot.
It could be Orochimaru. He might be interested in the baby's unique chakra, thinking he can use it for his experiments or to gain more power.
It could be Hinata. Since they are in a relationship in the original series, it would be a natural choice. Hinata would be a loving and caring mother, and her gentle nature would be a great influence on the baby.