i came here after reading the wn, the wolrd building in this novel is quite good compared to other wn in this genre, ngl i stayed because of the wolrd building.
due to red plague the ratio of female and male in this world is 1:30, because of that there increase in competition among women in this wolrd, they evolved to become more agresive and lustful.
They will do everything to get their prey, on the other hand man of this world evolved to become more meek and scared at the first sight of predaror. Funily enough this development led to an increased ability of the men to look like girl for camouflage