Overall, the story in 'When It Rains Worm' fanfic is full of mystery and adventure. The author creates a tense atmosphere where the rain of worms brings various challenges and opportunities for the characters. There are also elements of friendship and courage that drive the narrative forward.
This phenomenon was known as the " aftereffects of reading ". When reading a long novel or anime, the reader would be immersed in the story and have a strong emotional resonance and sense of substitution. It would often produce some emotional fluctuations and behavior reactions, such as thinking about the plot, recalling the characters, imagining the scene, and so on.
Sometimes, when readers read or watch novels or anime, they might suddenly think of certain plots or characters, causing emotional reactions such as crying. This phenomenon could also be due to the readers being influenced by the storyline or the emotions of the characters in the process of reading or watching, resulting in emotional resonance and emotional investment.
The aftereffects of reading were a relatively common reading experience. Although it might affect reading efficiency, it could also bring about a rich emotional experience and thinking.
It could be a metaphor for how problems tend to accumulate when one bad thing happens. Like if you lose your job and then your car breaks down all at once.
Maybe it's because the rain creates certain conditions that are favorable for the monster. Like, it could be that the moisture or the sound of the rain triggers something in the monster.