First, be careful with your activities. Avoid doing things that might put excessive and sudden pressure on the anal area. For example, don't jump around carelessly on hard surfaces. Second, when it comes to medical procedures, make sure you choose a reliable and experienced doctor. Also, always follow proper hygiene in the anal area to prevent infections that could lead to pain.
One could be a story of someone who had a very bad experience during a medical procedure in that area. For instance, if the doctor was not gentle enough during an anal examination. It can be extremely painful and leave the patient with a lot of trauma. Another might be a case where someone tried a very extreme sport or activity without proper preparation that put excessive pressure on the anal area, like some rough and tumble acrobatics gone wrong.
Rest is also important. Avoid sitting or standing for long periods of time as this can put pressure on the painful area. If the pain is due to an injury, it's important to let the area heal. Gentle exercises like pelvic floor exercises can also help in strengthening the muscles around the anal area over time, which can help prevent future pain.
One common experience in first painful anal stories could be due to constipation. When a person is severely constipated, the passage of hard stools can cause pain in the anal area. Another could be from a minor injury during strenuous physical activity like cycling for a long time without proper padding.
Rather than engaging with potentially inappropriate fanfiction, it's better to look for fanfiction that promotes positive values, such as friendship, teamwork, and character growth in the context of the Jaune and Ruby relationship.
One possible story could be that a man found out his wife was involved with a stranger in a way that made him feel cuckolded. He felt an extreme sense of betrayal and loss of trust. It was painful as he had to face the reality that the person he loved and trusted had such a relationship with someone he didn't know.