Well, one possible plot could be a character getting food poisoning and the story revolving around their friends or family taking care of them during this difficult time.
Well, it's a very odd concept. Maybe a plot could be that Batman gets poisoned and as a result has diarrhea, which then affects his ability to fight crime in some comical or inconvenient way.
There may be very few, if any, pieces of fanfiction directly centered around vomiting and diarrhea. Fanfiction usually focuses on more appealing aspects of characters and their relationships. You might be better off looking for stories where a character gets sick in a more general sense and then expands your search from there.
Definitely not. These types of stories involve rather unappealing and potentially nauseating elements. While adults may be able to tolerate and even find some sort of creative or thought - provoking aspect in such fantasy stories, children are not likely to have the same reaction. Young kids are more sensitive to these kinds of topics and it could have a negative impact on them, such as causing discomfort or bad dreams.
One way is to add a touch of mystery. For example, if the vomiting and diarrhea are symptoms of a strange curse in a fantasy world. The characters then have to go on a quest to find the source of the curse and break it. This adds an element of adventure to the otherwise unpleasant topics.
One possible cause could be food poisoning. Maybe the cafeteria food was not cooked or stored properly. Another reason might be a virus or bacteria that is spreading around the school. For example, if students don't wash their hands well after using the toilet, they can easily pass on germs.
In fanfiction, it might be due to a magical spell gone wrong. For example, if a wizard was experimenting with a new spell and it backfired on a bystander, causing their stomach to become upset and leading to diarrhea. Another possibility is that the character is allergic to something in the new environment they've entered in the story. This could be a new type of plant or a strange potion ingredient.
One possible reason could be that he was poisoned. In the wizarding world, there are many dark spells and potions that could cause such a reaction. Another reason might be extreme motion sickness if he was on a wild magical ride, like on a particularly unruly broomstick or a flying magical creature.
Spicy food is often a culprit in such stories. If a person is not used to very spicy dishes and consumes a large amount, it can irritate the digestive tract and result in hot diarrhea. Also, food allergies can play a role. For example, if someone is allergic to certain types of nuts or shellfish and unknowingly eats them, it can cause digestive issues including diarrhea.
Stress can also lead to it. A woman under a great deal of stress might experience changes in her digestive system, resulting in diarrhea. Her body's normal functions can be disrupted, and the gut may not work as it should.
A plot could also revolve around the friends starting a business together. They have different skills and personalities, and they need to learn to work together to make the business a success. There will be arguments and reconciliations during the process.