When you’re undertaking strenuous exercise and your nipples are chaffing in a top/singlet (usually of a light colour) and you bleed regularly (but not profusely) due to friction.

It is likened to the female reproductive process due to the unruly nature of the bleeding and the lack of sympathy from men.... HAHA, YOUR NIPPLES ARE BLEEDING LIKE DONKEY TEARS
Simon: Wow, John is about to come under 3 hours for his marathon, what an achievement!
Dimitri: An achievement!? What about the nipstruation that has the emergency services sweating like an Eskimo in Singapore?
by Shoogy January 7, 2020
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