"Help meeeee!" On her way home from shopping, Sumire passes by a factory and hears a cry for help. There she finds her son's friend, handcuffed and unable to move. It seems he is the victim of her son's prank. "The key is tied to my penis." Sumire is taken aback by her son's friend's words. Deciding she has no choice but to do it in order to settle the matter peacefully, she pulls down his pants, but... Sumire is faced with a hard, erect penis in the midst of puberty.