You should firmly tell them that this is not an appropriate topic and you don't want to hear it.
Politely tell them that this is not an appropriate topic for conversation.
Tell them firmly that this kind of story is not acceptable to be shared. Explain that it involves inappropriate content and violates others' privacy. For example, 'This story is inappropriate and disrespects the privacy of others, please don't share it.'
Tell them firmly that you don't want to hear it. It's inappropriate and unethical.
Tell them firmly that this is not an appropriate topic to share and that it makes you uncomfortable.
I would immediately interrupt and say that this is a private and inappropriate matter that should not be shared. It's important to set boundaries and uphold good taste in conversation.
Politely tell them that this is not an appropriate topic for discussion.
Immediately change the subject. You could say something like 'Hey, that's not a good topic. Have you seen any interesting movies lately?' This shows that you don't want to engage in such inappropriate talk. Also, it's important to convey that this kind of story is not acceptable in a normal conversation without being rude.
Tell them firmly that you are not interested in hearing such vulgar stories. You could add that it makes you uncomfortable and that you would prefer to have a positive and professional conversation. For instance, 'I'm not into this kind of stuff. Let's keep the conversation clean and work - related.'
Definitely not. We should respect the boundaries of privacy and propriety. Sexual stories, especially those with a very personal and potentially invasive nature like this one, have no place in general conversation. They can also be disrespectful to the individuals involved.
Stop them immediately. Politely but firmly tell them that this is not an appropriate topic for discussion.