There had once been a period when Human Civilization vigorously promoted population growth. The "Amorous Breeze" of those days had arisen from that. Later, as technology advanced, many emerging technologies were applied in this area.
To promote population growth back then, humanity had indeed put considerable effort into it, which in turn gave rise to many gene technologies based on this need.
Greatly enhanced endurance and pleasure were products of genetic technology from that era. Humanity identified the relevant gene expressions and edited them. Anything based on genes could be inherited, so after the earliest generation of humans underwent such modifications, later generations naturally possessed these abilities.
The combination of bigger and stronger with softer and more supple reflected the state of Human Civilization's internal society during that period. Coupled with humanity's later enhancement of its own strength, three or four hours was the minimum under normal circumstances, while in Overclock Mode, more than ten hours was hardly unusual.
Most importantly, throughout it all, that primal joy between them never faded. The wild frenzy and ethereal beauty carried through the entire process.
Perhaps this was one reason humanity had always been reluctant to alter the direction of bodily evolution. Call it vulgar taste or the ultimate truth of higher life—there would always be many who revered this path.
From a scientific perspective, humanity remained far from being able to create new life through its own intelligence. Thus, the mystery of life's birth continued to be admired.
Of course, admiration did not mean people were controlled by these primitive genes. It was entirely the result of humanity's own genetic modifications, with no adverse effects on individuals' daily lives or work. Instead, it became a pleasant diversion and a kind of mental boost.
In fact, the Partner System practiced in human society