Momoko is a devoted mother who single-handedly raised her only son, Shuichi, pouring all her love and strength into him. However, her parenting led Shuichi to become increasingly selfish and spoiled, culminating in him bullying and extorting his classmate, Hinomori. When Momoko discovers this, she secretly approaches Hinomori to apologize on her son's behalf. But consumed by a desire for revenge, Hinomori forces her to offer her body as compensation. Meanwhile, completely unaware of what's happening, Shuichi naively says, "Hey, lend me your mom for a bit," driving the story into deeper darkness.