Many young women like sharing details of their sex lives with their friends, including details about the anatomy of their partners. Those friends then talk about it with others and so on.
I don't know why anybody thinks this is fine. No woman would like their partner to share details with their friends, so why do they think it is fine for them to do it?
One of the most important things children are taught is to treat others how they would like to be treated; do not do something to others that one would not do to oneself. So why on Earth do women and girls think it is fine to betray their partners' privacy like this?

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