A second-year student at a London high school tells the super sleuth that he has a pipe that belongs to the school and that he can communicate by human speech. The super sleuth asks the student why he looks so serious, and the student replies that he was at the swimming pool until the end of class at 12:20, when he left to teach. He says that the last person who had the keys to the pool building was the dog, who was the only person to see Kiuchi sensei emerge from the bathroom, and no one could believe testimony from the dog. The student says that if he really wanted to play detective, he could just write his name and grade on a piece of paper, and then he could go home and tell his friends that he did it. He tells his friend that he had been at the pool from 12:20 to 12:20 and that his alibi is sound. He also says that there is still the text message from marushi, but he doesn't know if he got it because he didn't return the message. He then says that he knows how the murderer divided the time by dividing it by five minutes, and he knows what to do now. He explains that the killer took the five minutes to rehearse the murder, and she kept the clocks and watches because she was keeping them for the whole month so that she wouldn't notice the difference between the time and the actual time. She kept them in the locker room because she rehearsed the murder. He goes on to say that if the killer had timed the murder in the prep-room, then they would have noticed the difference in the time between the actual and the time. He adds that if this is the way the killer did it, then the bell in the room would have been set to go off, and they would not have noticed that something was off. He asks if he can go into the prep