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Goro Koizumi looked at the door with a puzzled expression in his eyes. After thinking for a moment, he said, "Strange, I come here often, but how come I've never noticed this door before? Judging from the decor, this seems to be an independent department. But what kind of department is it?"
Goro Koizumi searched nearby and found a room number plate on the ground that had been stepped on a few times. Picking it up, he saw it read "Public Security Section Zero!" He scratched his head and said, "Could this department be called Public Security Section Zero?"
Then Goro Koizumi hung the room number plate he was holding onto the door fixture, and it fit perfectly with the marks on the door. He was somewhat astonished and said, "I'm familiar with all the departments in the Metropolitan Police Department. How come I've never heard of this Public Security Section Zero, and what are their duties?"