Ranran, who desperately wants to marry her boyfriend, finds him hesitant about tying the knot. She hatches a plan: if she gets pregnant, he'll have no choice but to marry her! But her attempts at conception are met with no success. Seeing her sister, who has been married for just a few years and already has multiple children, sparks an idea in Ranran's mind. Her sister, after a previous divorce where she couldn't conceive with her ex-husband, has been blessed with multiple births since marrying her current husband. Ranran decides to exploit this, scheming to get creampied repeatedly by her brother-in-law in a devilish quest for pregnancy...