It began in China. Sex-selective abortion meant that China had a large surplus of men, many of whom would be forced to spend their life single.

Chinese health specialists noticed an ongoing increase in suicides among young men, who due to a low income had no chance of a long term relationship. The sex ratio of 1.1 men per women essentially meant the eradication of the poorest 10% of China men from the Chinese gene pool.

Because suicide destabilizes society, government sought a solution to the high number of suicides in Chinese cities. Prostitution was legalized, but it turned out not to lie in the nature of the Chinese man to seek out prostitutes, and hence little changed. Polyandrous marriage was legalized, but old taboos are hard to change.

The Chinese government eventually resorted to a radical solution, that doctors and psychiatrists had secretly been practising already for quite a few years. Chemical celibacy. Chemical celibacy was used to refer to pharmaceutical interventions that managed to suppress the male drive to seek out a relationship and procreate. This allowed men to live lives in which reproduction did not distort their lives. It was entirely reversible, and side effects were almost non-existent.

At first it was considered shameful, but eventually it became accepted. Many families had a chemically celibate son who was happy taking care of his elderly parents and enjoying life with his (overwhelmingly) male friends. It rapidly became a trend that young adolescents with a promising career ahead of them entered chemical celibacy, to prevent them from being distracted by their natural drives. Eventually, those young adolescent grew up to become young men, who saw no reason to quit their treatment.

Chinese women did not enjoy this new trend too much, as it limited their partner options. The days where they could reject any man who did not have a house and a car were soon over.

Chinese women at first tried ridiculing what became known as "cebs". They declared them to be gay, effeminate, losers, and various other insults. Chinese cebs overwhelmingly ignored these insults, and more and more men chose to undergo treatment, as it wasn't hard for any single man to convince his doctor to give him a subscription for these libido suppressing chemicals.

Chinese women in the media reminded Chinese men that they are incredibly "privileged" in Chinese society, because they earned about 5 or 10% more money, most politicians were male, and childbearing and menstruation were incredibly painful, but Chinese men were not particularly impressed, and still many chose to chemically eliminate their desire for women. Estimates by now were that about 20% of men between 20 and 40 years were "chemically celibate".

The next phase in the battle between the genders became self-sabotage. In an effort to make Chinese men angry, Chinese women began sleeping with black and white men from abroad. Chinese men did not feel particularly angry, and instead retaliated, by adopting third world babies. Chinese cebs cynically remarked that this was a simpler way of continuing one's lineage than bothering with the expensive rituals of restaurant visiting and gift-showering.

The Chinese government, alarmed by the ongoing collapse of Chinese society, responded by closing China off from the outside world. Tourism and education in China became difficult, and adoption from foreign countries was forbidden.

Meanwhile, men in other countries had begun to grow attached to the idea of eliminating their dependence on women as well. Men in India, troubled by the same gender imbalance as China, overwhelmingly turned to ceb-dom. In Europe and the US, cebs became a growing subculture as well, and associated with certain type of jobs, such as programming and engineering.

In China, women had became divided between those who sought to outlaw chemical celibacy altogether, and those who demanded the same right as men to chemical celibacy. It turned out however, that the female desire to be "desired", "taken care of" and "protected", was a lot more complex and innate from a biological perspective, than the male procreation drive, which is largely a product of testosterone. But doctors promised that soon chemical celibacy would be an option for women as well.

It suffices to say that the nuclear family became affected by this new development as well. Chinese fertility rates declined immensely at first. Later however, procreation in China became divided into two groups. On the one hand were Chinese men who paid large sums of money to raise children in African women who served as surrogate wombs. It need not be mentioned what the gender of these children was. It wasn't uncommon for cebs to choose to raise literal clones of themselves. The Chinese government considered all of this an international embarrassment, and research into artificial wombs accelerated.

Chinese women on the other hand, were divided between wishing to raise "real men", and women like themselves. Hence, Chinese women gave birth to about evenly as many boys as well as girls. Some of these boys rebelled, no longer as a result of being expected to earn obscene amounts of money from their cubicle jobs if they ever wished to get laid, but as a result of the large social pressure they felt, and hence became cebs as well. As a result, the number of cebs continued to rise, until finally halfway in the 22nd century, cebs had become the majority of the Chinese population.

Eventually, men and women evolved into two asexually reproducing species, whose mutual hatred consumed the planet in a nuclear holocaust.