Lewd skill in a filthy world - Chapter 1. Global System Online

Amid a world war, with his awakening to powerful special abilities (Soul Armor Abilities), Kamiya Yuusuke, conscripted into the military at the age of 10 due to this newfound power, continued to achieve numerous victories on the challenging battlefield. As a result, at the age of 15, he held the position of Brigadier General.Despite traversing battlefields worldwide, he finally managed to return to Japan. The joy of returning home was short-lived, as news of an underage boy in the military started to leak to the public. In response, the military high command ordered Yuusuke to attend a military school called the Special Operations Soul Armor Academy and undergo a revision of his military records.Yuusuke, secretly pleased at the prospect of reclaiming his youth, faced numerous troubles, whether due to the nature of the unique school or perhaps because he had been in constant battle since childhood. What will happen to his relationships with strong-willed girls such as his half-silver-haired childhood friend, the older sister officer who is his work partner, and the tsundere honor student of the same age?

After 2000 years has passed, the ruthless demon lord has just been reincarnated! But his aptitude at an academy for nurturing candidates for demon lords is, “Inept”!?

After a tragic accident that claimed the lives of his parents and little sister, Leo, just 17 years old, found himself shouldering all responsibilities alone.By some miracle, he survived the past four months on his own—attending high school, juggling multiple part-time jobs, and enduring sympathetic gazes that pained him.The only respite he found was in books, which offered him an escape and some semblance of joy.One day, while engrossed in the book 'Path of Heroes: Battle Against the End,' his life took an unexpected turn.Halfway through the story, he inexplicably found himself transmigrated into the world of Path of Heroes, inhabiting the body of Azriel Crimson—a character never mentioned in the story's first half.An extra.Someone seemingly irrelevant to the plot.Unfortunately—or perhaps fortunately—fate had other plans, and Leo soon discovered that being a mere extra was not his destiny after all.

An Individual from Earth finds themselves in the Shinobi World, equipped with a Scientific System. From that moment, he delved into scientific research far ahead of its time.