With @papabirdurskeks we love to headcanon that Killgar is exagerating when saying they all are born from the depths of the planet Killgaria if so they wouldn't have fathers and sons, nipples or genitals, and he wouldn't have been a child before but born direvtly as a warrior adult like he claims, so we headcanon there actually are female Killgarians but they just look and sound exactly like the males. Titties out because they are pecs just like the guys, just as strong, mean and aggressive, deep voices, and their genitalia follows the same logic as female hyenas so it's hard to differentiate them down there too. However as soon as the males were introduced to other females from other species, a lot of them grew attracted by their feminity (and boobs) and a lot prefer them like Killgar which contributed to the species' eventual extinction, only the most traditional ones and "connoisseurs" attracted to "real women" still going for their own females (Mat's Goregoth to my Hysterax)