Their interaction could be full of conflict at the beginning. Severus is a proud and often prickly character. When Harry tries to approach him, Severus might lash out, thinking Harry is there to mock him. However, Harry's persistence pays off. He manages to show Severus that he has no ill intentions. Eventually, they start to communicate more openly. Harry might even confide in Severus about some of his own struggles at Hogwarts, which makes Severus realize that they are not so different after all.
At first, Severus would probably be very suspicious of Harry. After all, Harry is an unknown figure suddenly appearing. But Harry, being the friendly person he is, would try to break the ice. He might start by complimenting Severus on his potion - making skills, which Severus is already quite good at even as a young boy. Their interaction would be a bit tense initially, but as they start to understand each other more, they could become friends or at least allies.
Harry would likely be empathetic towards young Severus. He knows about Severus' difficult life at home and being bullied at school. So he would try to offer support. Severus, on the other hand, might see Harry as a bit of an enigma. He would be curious about Harry's knowledge of magic, which seems different from what he has learned so far. As they interact more, they might exchange magical knowledge, with Harry introducing some new spells he has learned, and Severus sharing his deep understanding of potions.
At the start, Snape would likely be quite suspicious of Naruto. He's used to a world full of secrets and might think Naruto is some sort of threat or spy. Naruto, being Naruto, would keep trying to break through Snape's cold exterior. He might start by complimenting Snape's skills in potions or magic. As time goes on, Snape might see Naruto's good heart and start to open up a bit more. They could end up having some interesting conversations about power, loyalty, and friendship. Naruto could tell Snape about his bonds with his friends in the ninja world, and Snape could share some of his own experiences with the Marauders from his school days.
In such a fanfiction, Harry might see the potential in young Severus that others overlooked. He could protect Severus from the bullies at Hogwarts. Harry, having experienced his own share of hardships, would understand Severus's situation to some extent and try to give him a better childhood, perhaps even guiding him to use his magic in a more positive way.
One possible plot could be that Harry, through some time - traveling magic, meets young Severus. Harry, knowing Severus' future, tries to befriend him and change his path. He could introduce Severus to different ways of using magic that are less dark - oriented, which might change Severus' perception of magic and his future relationships in Hogwarts.
In many fanfictions, their interaction starts with suspicion. Snape is a very guarded character, and a female Harry Potter would be an unexpected presence. So, at first, he might be cold and distant.
In some fanfictions, Snape might share some of his knowledge about the wizarding world's secrets with Harry. Maybe he tells Harry about certain spells or magical artifacts that could help Harry in his fight against Voldemort. This act of sharing knowledge is a way of being nice as it gives Harry an advantage in his battles.
A lot of fanfic writers will create unique storylines for Snape's courtship. They might introduce an original character who manages to break through Snape's tough exterior. His courtship would then involve him struggling with his own insecurities and his reputation. This character might see the good in him that others overlook. There could be moments of tension and misunderstanding, but also deep, meaningful conversations as they get to know each other better.
Often in fanfiction, the ring can be a plot device. It could be that Harry Potter unknowingly has a connection to the ring, and Severus Snape has to keep it from falling into the wrong hands. This creates a situation where Snape has to protect both Harry and the ring, leading to some tense and interesting storylines.
If Snape's family were to interact with the Malfoy family, it would be a complex situation. Snape had ties to the Malfoys in the past, but his new family might have different values. His family could try to distance themselves from the Malfoys' pure - blood supremacist views. Or, they could try to reform the Malfoys through their own positive influence, leading to some tense and thought - provoking interactions.
Severus could become more confident. With Harry's support, he may not be as shy or withdrawn as in the original story. He might be more open to making friends outside of Slytherin.
Hermione would probably be one of the main characters to interact. She might be horrified at first to see Harry in such a situation and would try to find a way to free him. Ron could also be involved, perhaps being more impulsive in his attempts to rescue Harry, which might cause some problems. Dumbledore too would likely play a role. He might have some knowledge about the situation that he's not sharing right away, and his interactions with Severus would be crucial in determining Harry's fate.