I love the description CriticalVolume wrote for this image. I’m sure you can get the gist from the pic alone, but he really sells it in the text.
The Kantisindi tribeswomen are a genetic offshoot of humanity; a single-gendered race of hedonistic desert women that are best known for their biological ability to store water in their breasts as an adaption to their arid environment.
Their breasts have a complicated system of osmotic regulation that isolates surplus water in their mammary tissue, preventing the rest of the body from being thrown into a state of hypotonic water shock from the vast excess of liquid. When beginning from a fully-laden state, most Kantisindi can function without water for up to twelve days even while engaging in extreme physical activity during the hottest parts of the day. If allowed to rest in the shade and conserve water, they have been observed to last more than a month without water before experiencing significant distress.