Seo Mina, a successful adult webtoon writer, might have a thriving career, but her dating life is a disaster. One fateful night, she discovers her boyfriend cheating on her with another man. In a chaotic attempt to retrieve her unused condoms, she tumbles into the Han River and is mysteriously transported back to the Joseon Dynasty!

Struggling to adapt to her new reality, Mina's fortunes take an unexpected turn when she sketches a provocative drawing of a naked man while working in the kitchens of a gisaeng house. Her bold artwork catapults her to fame, and she seizes the opportunity to create Joseon's very own adult webtoon: a tantalizing collection of erotic drawings.

Her work becomes the talk of the capital, captivating the women of Joseon. Just as Mina basks in her newfound notoriety, a mysterious stranger approaches her with an audacious proposition: "From now on, draw erotica for the sake of Joseon."

Faced with this absurd yet thrilling challenge, Mina's adventure in the past is just beginning.