For centuries, Japanese culture was defined by a hyper-masculine warrior ethos, epitomized by the samurai. This ideal emphasized loyalty, discipline, and stoicism, with surrender considered the ultimate dishonor. This warrior spirit permeated society, influencing military conduct and national identity. During World War II, Japanese soldiers exhibited extreme dedication, with surrender rates significantly lower than those of other nations. Kamikaze pilots, undertaking planned suicide missions, further demonstrated this cultural valor. Even the atrocities committed by Japan during the war can be partly understood through this lens, where captured enemies were viewed as less than human due to the cultural abhorrence of surrender.

The abolition of the samurai class in 1876 did not eradicate these values. Instead, the principles of Bushido, the samurai code, continued to shape Japanese masculinity. This warrior ethos was reinforced through education and military training, solidifying a national identity where death was preferable to capture or dishonor. This mentality, however, contributed to Japan's devastating defeat in World War II, resulting in widespread destruction and significant loss of life, particularly among military-aged men.

Following the war, the Allied occupation initiated a deliberate dismantling of militaristic culture. Textbooks were rewritten, nationalist films were banned, and democratic values were promoted. This period saw the emergence of the "salaryman" as the new masculine ideal. These men channeled the loyalty and self-sacrifice previously directed towards the emperor and feudal lords towards their corporate employers. The language of Bushido—loyalty, endurance, and sacrifice for the collective good—was applied to corporate life. Salarymen worked long hours, often six days a week, enduring grueling commutes and mandatory after-work social engagements. In return, companies offered lifetime employment and job security. This model fueled Japan's rapid economic recovery, transforming the nation from post-war ruins into the world's second-largest economy.

However, this system came at a significant cost, leading to "karoshi," or death from overwork. Men in their prime succumbed to stress-related illnesses and suicides. Simultaneously, wives managed households and child-rearing alone, effectively running single-parent families while married.

The economic bubble burst in 1990, ushering in Japan's "lost decades." Lifetime employment vanished, replaced by temporary and part-time work. The promise of security offered by the salaryman model evaporated, rendering the sacrifices of these men increasingly untenable. Concurrently, women were entering the workforce in greater numbers, reducing their economic dependence on husbands. This shift allowed women to re-evaluate partnership expectations.

The ideal of masculinity began to change, influenced by popular culture. Female manga artists popularized "bishonen"—slender, androgynous, emotionally expressive male characters—who were the antithesis of the stoic warrior or the overworked salaryman. As the salaryman model failed to guarantee a middle-class life, women began prioritizing partners who were kind, gentle, communicative, and willing to share domestic responsibilities and childcare.

In 2006, the term "grass-eating men" or "herbivore men" was coined to describe a generation of young Japanese men who adapted to this new reality. These "modern men" are often well-groomed, fashion-conscious, and gentle, showing less interest in aggressive romantic pursuits or climbing the corporate ladder. Many live with their parents into their thirties, prioritizing hobbies and personal interests over traditional markers of success like cars or houses.

This shift has contributed to a significant decline in romantic relationships and sexual activity among young Japanese men. Data indicates that a third of Japanese men under 30 are virgins, and nearly half of men in their twenties have never been on a date. This "love withdrawal" is attributed to economic instability, mixed messages from women seeking gentle partners yet still expecting providers, and the collapse of traditional masculine roles. The warrior and salaryman paths proved unsustainable, leaving a void in masculine identity.

The consequence of these societal shifts is a growing sexless society and a declining birth rate. Japan's fertility rate hovers around 1.3 children per woman, significantly below the replacement level of 2.1. The population has been shrinking since peaking at 128 million in 2008, with deaths now outnumbering births by over half a million annually. Projections suggest Japan's population could fall to 63 million by 2100. Adult diaper sales have surpassed baby diaper sales since 2011. Even within married couples, over half report being effectively sexless, citing work fatigue or a lack of interest.

This demographic crisis poses a significant threat to Japan's societal functioning. The aging population, with over 10% of Japanese aged 80 or older, places a substantial burden on a shrinking workforce. Government initiatives to encourage marriage and childbirth have yielded limited success, as the fundamental social contract appears broken.

Japan is not alone in facing these challenges. South Korea's fertility rate reached a global low of 0.72 in 2023, with its youth reportedly giving up on dating, marriage, and children. China has taken measures to ban "effeminate" men from television, attempting to promote a more traditional masculine image. The West is also experiencing declining marriage and birth rates, with the United States showing a significant percentage of young adults abstaining from sex and living with parents. These trends suggest that Japan's experience, while perhaps accelerated, reflects a broader global pattern of evolving masculinity and declining intimacy. The future of healthy masculinity remains uncertain, particularly as cultural definitions of manhood become obsolete without clear replacements.