No, it is completely inappropriate. Such topics are private and vulgar, and not suitable for general discussion. We should focus on positive, healthy and respectful conversations.
Sharing such stories is completely inappropriate and unethical. It involves violating the privacy and respect of others in a very serious way. It also goes against moral and social norms.
One way is to set clear boundaries. Let others know that you are not interested in such vulgar topics. For example, you can say 'I prefer to talk about positive things, not this kind of stuff'.
Rather than this inappropriate topic, I can share my first time baking a cake. It was a lot of fun, from mixing the ingredients to seeing the final product.