Chawonidonghaessdeoni Tteokhyeopji Gosuga Doeeossdago?

Kang Yoo, A novice martial arts web toon novelist, flops his first novel. Under the impression that his career was already ruined. He starts writing a new novel with his own personal tastes he started an adult murim novel series full of milfs called “Colorful Warriors”. However, Colorful Warriors suddenly gained positive feedback and an enormous following. While feeling burdened by the unexpected reactions, Kang Yoo was accidentally transported into his own novel. In there, he meets the women he had always admired back in his world, learning to cultivate the “Art of the Snake,” which can only become stronger through yin and yang harmony(sex)…

(Source: Lezhin, translated)