Ema and Yuya are a loving couple. Yuya is an extremely cowardly person, and Ema, who is a big sister type, is overprotective of Yuya. One day, when Yuya is being mugged by a local DQN, Ema happens to pass by and chases him away. The DQN, who holds a grudge, identifies the house and later shows up at Yuya's house when he is not there, and assaults him with his big ass. He forces Ema to kneel naked and apologize...