Monster Girl Development Master.

Zhuang Sen was transported to another world, where extraordinary bloodlines were revered, and the strong could even transform into dragons or titans, capable of taking on thousands single-handedly.
But Zhuang Sen was very dissatisfied. How could a mere dragon compare to a dragon maiden?
Monster Girl Development System, Activated!
Thus, the devout and holy nun transformed into the alluring and muscular snake girl Lamia; the quiet young scholar became a languid and seductive vampire girl; the cunning and shrewish little imp sister became the charming and adorable Happy; and the haughty princess became a red dragon girl…
From weak slime girls to powerful dragon girls, from holy angels to alluring demon girls, wherever Zhuang Sen's territory expands, monster girls proliferate like a plague.
What? You're saying low-level monster girls are too weak and their bloodline limits them so they can never become stronger?
It's simple, I'll help her evolve!
After saying that, Zhuang Sen grabbed the monster girl and she instantly evolved. As the light of evolution faded, another hunter joined the hunt.
Zhuang Sen is 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!"