A world with a severe overpopulation problem where 80% of the population is Male for some reason. Because of this, any man 18 or older is allowed to kill each other! There is a mandatory tattoo that a man must get when they turn 18 that indicates they are 18 or older and can kill or be killed. Trans men are considered men (and must get the tattoo after transitioning), and Trans women are considered women in this setting. Men killing women, women killing men, and women killing each other is still illegal.

Additional tags/keywords: killing yaoi bi ryona blood gore fetish kink extreme