How does Snape sending Harry a howler play out in fanfiction?

Well, it could vary a lot depending on the author's imagination. Sometimes it triggers a series of conflicts and misunderstandings, while in other stories, it might bring them closer together.

Harry might be initially shocked and embarrassed. A Howler is a very public form of scolding, and in front of all his friends and classmates, it would be a humiliating experience for him.

It could create a lot of drama and tension. Maybe it leads to a big argument or a revelation of some hidden secret.

The fanfiction usually shows Snape being quite shocked and embarrassed when he gets the howler. It might lead to some interesting character developments and interactions.

Hermione could be the sender. If Snape has made some unfair judgment in class against Gryffindor students, Hermione, with her strong sense of justice, might send a howler to him to voice her protest.

Voldemort might initially be furious. He's not used to being challenged in such a blatant way. He could try to destroy the Howler immediately in a fit of rage.

Snape's reaction could be quite mixed. On one hand, he might be angry at Dumbledore for not doing more if he knew about the abuse. He may also feel a strange sort of empathy towards Harry. After all, Snape himself had a difficult childhood. So, he could start to be a bit more lenient with Harry in his classes and try to subtly offer support.

In fanfiction, Harry Potter's psychology often gets explored in different ways. For example, his trauma from facing Voldemort and losing loved ones can be delved into more deeply. Some fanfics might show how he copes with the fame that he never really wanted, and his insecurities that are often masked by his heroic deeds in the original books.

Often, Snape's punishments are related to Draco's misbehavior in class or within the Slytherin house. For example, if Draco is caught bullying other students, Snape might make him do extra assignments related to dark arts defenses. This is because Snape wants Draco to understand the importance of self - control and not using his pure - blood status to intimidate others.

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.