There is no evidence to suggest that such activities occur in a gym environment. Gyms have rules and ethics in place to maintain a proper and respectful atmosphere for all members. This kind of description violates the basic norms of a public fitness place.
In such stories, you might find themes of taboo exploration and the challenge of societal norms. But keep in mind that the content can be highly provocative and not everyone's cup of tea.
This is completely unethical behavior. Any form of sexual act outside of a consensual and appropriate relationship context is unacceptable, especially when it involves disrespecting a spouse in such a blatant way.
No. Such stories are highly inappropriate and violate social norms of decency. This kind of description involves private and vulgar content that is not suitable for public discussion or sharing.