Mother Sakura, who deeply loves her son Yuuichi, is overwhelmed one day by unfamiliar and complex emotions upon learning he might get a girlfriend. These feelings go beyond the boundaries of motherhood—taboo desires she can no longer suppress. Soon, Sakura becomes determined to guide her virgin son into manhood herself, resolving to teach him about women using her own body. This first step ignites an incomprehensible bond between mother and son. Their bodies can no longer stay apart. A forbidden love story begins quietly between parent and child, as they repeatedly engage in creampie intercourse.