He was transported to Japan in 1912, only to discover that this bizarre world was inhabited by yokai (supernatural beings), and that as a samurai, he had an obligation to slay them? Fortunately, despite this hellish start, Taira no Harunobu awakened a system that allowed him to draw unique sword techniques and items from various works by training disciples! Under his careful tutelage, the older sister next door learned Thunder Breathing and Lightning Return, becoming the Inari Soul Sword Saint; the little girl who used to roam the streets mastered Laurent's Mind's Eye Blade, becoming a peerless swordswoman with every strike finding its opening; and the noblewoman lawyer was inspired by the Ashina style, mastering the profound principle that everything can be a sword… Huh? Why are there only girls in the dojo? Nonsense! Isn't he a man?! — So said Taira no Harunobu, the Swift Wind Swordsman, the Eternal Sword Saint, and the Guardian of the Samurai Clan.

Zhuang Sen transmigrated to another world, a world where extraordinary bloodlines reign supreme, and the strong can even transform into dragons and titans, capable of taking on thousands single-handedly. But Zhuang Sen was dissatisfied. What were mere dragons compared to dragon girls? "Monster Girl Development System, activated!" he thought. Thus, a devout and holy nun transformed into the alluring and massive snake girl Lamia; a quiet young scholar became a languid and seductive vampire girl; a cunning and shrewish little imp sister became the charming and adorable Happy; a haughty princess became a red dragon girl… From weak slime girls to powerful dragon girls, from holy angels to bewitching demon girls, wherever Zhuang Sen's territory expanded, monster girls proliferated. "What? You say low-level monster girls are too weak, their bloodlines limiting them from ever becoming stronger?" "Simple," Zhuang Sen said, "I'll help them evolve!" With that, Zhuang Sen grabbed a monster girl, and she instantly evolved. And as the light of evolution faded, another hunter joined the hunt. Zhuang Sen, only fit for the strong! Years later, the legendary King of Endurance, the Father of a Hundred Races, and the King of Kings, Zhuang Sen, looked at the monster girls scattered throughout the world and uttered his final words: "Quack, don't mess with it!"