Moko is living alone in Tokyo for two weeks during her summer cram school course, and visits the weekly apartment where she will be living. Though it is only temporary, she is excited about her new life in Tokyo... but she feels uneasy when she sees a huge amount of trash scattered next to her room. The apartment next door is occupied by Shimonuma, a dirty older brother who can masturbate continuously even after climaxing and doesn't clean up after himself. Moko musters up her courage and goes to tell Shimonuma, but...