Houtou Kizoku wa Moto Outaishihi to no Haramasekon de Isogashii

Artie, the second son of a viscount family with a reputation as a "womanizer and dissolute," is to marry Giselle, the daughter of a prestigious marquis family and former crown princess. After being divorced by the crown prince unilaterally, Giselle, who now governs her family's marquisate, needs to produce an heir to the marquisate, and therefore desires a new "husband"—specifically, a "man with plenty of experience who can quickly impregnate women."

"Would you marry me with the intention of having children?" Artie readily accepts her proposal and becomes her husband, but from the very first day of their marriage, he is taken aback by Giselle's workaholic and overly strict and ascetic demeanor. He faces their wedding night with apprehension about their future married life, but his eyes are captivated by Giselle's daring nightgown and alluring figure as she awaits him in the bedroom. And then, "'Marriage of husband and wife' is a duty necessary for the survival of the family and the nation. It is something that must be endured and done diligently." Her attitude, showing such ignorance of "pleasure" despite having been married before , caused his reason to crumble. "I will teach you everything you couldn't do with the Crown Prince (your ex-husband). I will teach you how to have pleasurable lovemaking so that Giselle can conceive my child."

A dissolute nobleman and a strict former crown princess. The two's "duty to make a baby" will not end until morning today either──…