Suppose Snape is at King's Cross Station waiting for someone. Hedwig flies in and circles around him. Snape, recognizing Hedwig, decides to follow her. She leads him to a hidden part of the station where there are memories or secrets related to Harry and his family. Snape and Hedwig's interaction then becomes a journey of discovery for Snape as he uncovers things he didn't know before, all with Hedwig as his guide of sorts.
In the fanfiction, Hedwig could be carrying a small parcel that she drops near Snape. Snape, out of curiosity, picks it up and discovers it has something to do with Harry. This could lead to a conversation - like interaction where Snape talks to Hedwig as if she can understand, expressing his mixed feelings about Harry. Hedwig could then hoot in response, almost as if she's giving her own opinion.
Perhaps in the fanfiction, Hedwig is lost near King's Cross Station. Snape, who is there for some mysterious reason, decides to help find Hedwig. As he searches, he starts to understand the significance of Hedwig to Harry and through this, his view of Harry softens a bit. It could be a story about unexpected connections and growth in Snape's character.
It could be a story where Hedwig serves as a sort of guide for Snape in the afterlife. Maybe she shows him the good he did that was overlooked in life.
Snape would probably start off being rather aloof. He'd observe the Avengers' behavior and abilities before making any real moves to interact. He could be sarcastic towards them, especially if they make assumptions about him or his magic. But as time goes on, he might start to see their value and open up a bit more, sharing some of his magical knowledge.
In some fanfiction, Voldemort and Snape interact in a very master - servant kind of way. Voldemort gives orders and Snape follows, but with a hidden agenda. For example, Snape might be subtly changing the Dark Lord's plans without him noticing.
Often, they start off as adversaries. For example, in many fanfictions, Snape's dark and brooding nature clashes with McGonagall's no - nonsense attitude. But as the story progresses, they might find common ground in protecting the students or in the face of a greater threat to Hogwarts.
Snape would likely be disdainful towards the Dursleys. He has little patience for Muggles in general, and the Dursleys' mean - spiritedness would not endear them to him. He might use his cold, sarcastic tone on them, leaving them confused and a bit frightened.
Maybe Hermione discovers a mistake in Snape's teaching materials (not in a disrespectful way). She approaches him after class to politely point it out. Snape, initially defensive, realizes she's right and commends her for her attention to detail. This could be a scenario that plays out in a classroom setting in fanfiction.
Snape might become more confident. As a king, he would have to take charge and make decisions without hesitation. His usual brooding and self - doubting nature might be replaced by a more assertive and commanding personality. He would also likely be more protective of his 'kingdom' or those under his rule, which could show a more noble side of his character.
Often, Hedwig develops a stronger bond with Harry in fanfiction. She might become more protective of him, going beyond just being his messenger. For instance, she could sense danger approaching Harry before he does and take actions to keep him safe. This shows her growth from a simple owl to a more complex character with emotions and instincts. Also, in some stories, she may develop relationships with other characters in the wizarding world, like the other owls or even some of Harry's friends, which further shapes her character.
In some fanfiction, Snape's portrait has the ability to possess or influence the living. This could be used for good, like helping a character perform a difficult spell, or for more devious reasons if the plot calls for it. It adds an interesting dynamic to the story as the living characters have to deal with this unexpected influence from the portrait.