Women and men or just women? If you’re asking about men, there’s a whole discussion about that on a question about it.
On the other hand, women have nipples because it’s the way in whig mammals breast feed.
I’ve also heard that men have nipples because when the body is forming inside of the womb the sex of the baby doesn’t start until a couple of weeks in. But during the previous time of development, the baby will have developed certain traits that include the nipples…
