They are not common. Literature usually gravitates towards topics that have broader appeal. Hypnotized little sister stories are rather niche. While there might be some short stories or even parts of novels where hypnosis is involved, it's not a typical plot device when it comes to a little sister character. It might be more likely to find in some experimental or indie literature pieces.
There could be a story where a little sister is hypnotized by accident. For example, she watches a strange, swirling pattern on an old TV screen that has some sort of hypnotic effect. As a result, she starts acting in a very different way. She might start speaking in a language she doesn't know or be able to do amazing physical feats like balance on one foot for a really long time. But then her older brother or sister has to figure out how to snap her out of it.
It is completely inappropriate. Erotic content has no place in proper literature or general consumption. It objectifies and disrespects others, and can have a negative impact on one's mental state and values. We should stay away from such materials.
No, such stories are not common at all. Hypnotizing someone into a different mental state, especially into the state of a little girl, is a very unusual and specific plot. Most stories tend to focus on more mainstream themes like love, adventure, or mystery.
Yes, there are. Hypnotizing someone into an inappropriate or unethical state, like pretending to be a little girl, can violate boundaries of respect and consent. It blurs the lines between normal, healthy relationships and can potentially lead to psychological harm or discomfort for the person being hypnotized.
The story might start with the sister's best friend being hypnotized during a strange eclipse. She starts acting out of character and doing things that are not normal. The sister realizes something is wrong and decides to seek help from a local wise woman. The wise woman tells her that the hypnosis is related to an ancient curse that was placed on their land long ago. To break the curse, they need to find three magical stones hidden in different parts of the village. The sister and some of her other friends then start a quest to find these stones. It's a race against time as the hypnosis on the best friend is getting stronger, and they must work together to save her.
One possible story could be that the sister's best friend discovers she has a special power to enter people's dreams. She accidentally hypnotizes the sister while trying to show off this power. In the hypnotized state, the sister reveals her deepest secrets and desires. The best friend then has to figure out how to reverse the hypnosis without causing any harm or revealing the secrets to others.
One story could be about a woman who discovers her husband has a deep - seated trauma from his childhood. She decides to hypnotize him to try and heal that part of him. As she does so, he slips into the mindset of a little girl. He starts to see the world with a child - like wonder again. However, this also causes some chaos as he forgets his adult responsibilities for a while, like going to work and paying bills, and they have to navigate through this new situation together.
A simple story could be that the sister's best friend has a magic pendant. When she touches it while looking at the sister, it hypnotizes her. The sister then starts acting like a character from a fairytale. The best friend has to use her wits and some other magical items she finds to break the spell. Maybe she has to go on a quest to find a special flower that can reverse the hypnosis.