It's not appropriate at all. In a healthy family environment, the relationship between mom and son is based on love, respect, and appropriate family values. Erotic stories are adult - oriented and violate the normal family ethical relationship.
The mother can calmly tell her son that it's a private item and he should respect privacy. For example, she could say 'Son, this is my personal thing, please don't look at it.'
Another plotline could be that the wizarding world discovers Harry's connection to Arwen and Middle - earth. This causes a stir as they try to understand what it means for their world. Some might fear the unknown powers he could possess, while others see it as an opportunity to expand their magical knowledge. Harry could be caught in the middle of this, trying to prove that his connection to Arwen is a positive thing and that he can use it to protect both his worlds from common threats like dark forces that could exist in both the wizarding world and Middle - earth.
I'm not sure about specific 'Harry Potter son of Arwen' fanfictions. You can try searching on fanfiction - related websites like FanFiction.net or Archive of Our Own. These platforms have a vast collection of fan - made stories, and by using the relevant search terms, you might be able to find some interesting ones.
My Son Is the Male Lead was an ancient romance novel written by the author, Du Xing's Life. The female lead was a single mother, Yun Jing. Yun Jing died in an accident at her son's 18-year-old coming-of-age ceremony and traveled to ancient China to become the wife of the Fuguo Duke's heir. She had just suffered a miscarriage by her husband's childhood friend's cousin, and in the process, she found out that she had traveled here with her son. Later, Yun Jing and her son moved in together. I hope you like this fairy's recommendation. Muah ~😗
In ancient times, when a concubine saw a legitimate son, they did not need to kneel, but when they met, they needed to bow to the legitimate son. A legitimate son was a son born to his wife. The specific rules of etiquette might vary according to the dynasty and individual circumstances.
In case of an accidental sighting, the son should respect his mother's privacy by averting his eyes and exiting the area. Afterward, the mother can approach the situation calmly. She can have an open and honest conversation with the son about the importance of privacy, how accidents can happen, but also stress the need to be more cautious in the future. This incident can serve as a learning opportunity for both of them to strengthen their understanding of personal boundaries within the family.