If one opens the map of Tokyo Metropolis, it will be discovered that Musashino City, Shibuya District, and Sumida Ward are essentially on the same line.
To go from UDI in Musashino City to the Tokyo Skytree in Sumida Ward, one must pass through Shibuya.
However, at this moment Kusanagi Ritsuko had not yet realized this; she was puzzling over the locations of Minami and Inomata Naoki on the map, searching for a connection between the two.
Meanwhile, Tokairin Yūko, who had finished her workday, was sitting on the subway heading for downtown Tokyo from Musashino.
Sitting in the subway, Tokairin Yūko first took out a makeup mirror to carefully check her appearance for the day, and having confirmed there were no issues, she then took out her mobile phone to send messages.
But Tokairin Yūko was not messaging Inomata Naoki, rather she was communicating with Qingdai.
