In the year 20XX, a being was born who transcended traditional gender boundaries. This baby, named Zero, possessed a "third gender," neither male nor female, and this new gender was named "Z." Under the watchful eyes of a team of doctors, Zero grew up. As Zero matured, they demonstrated astonishing athletic abilities and a well-balanced physique, becoming a person of strong influence in their surroundings. During school years, Zero excelled in sports, becoming immensely popular. Later, after graduating from university and entering the workforce, Zero unexpectedly experienced morning sickness and discovered they were pregnant. The astonished medical team conducted further investigations and found that Zero could conceive simply from a relationship with a woman. Moreover, Zero possessed the unique ability to impregnate a man. This discovery and the resulting "triangular gender dynamic" sent shockwaves through society, fundamentally challenging conventional concepts of gender. Thirty years after Zero's birth, babies with the Z gender began to be born worldwide, eventually making up about one-third of the population. To accommodate this new gender, countries were compelled to undertake comprehensive revisions to their laws. As time passed and the Z gender matured, unprecedented forms of love and family, such as "triangular marriages" involving men, women, and Z individuals, became more common. As this new era unfolded, with "man," "woman," and "Z" supporting and keeping each other in balance, people gradually began seeking paths toward love and coexistence beyond the constraints of traditional gender. The wave of change sparked by Zero’s existence challenged the world to reconsider its values and beliefs.