Youko and Airi's next stop is Umihotaru, a rest stop in the middle of
Tokyo Bay famous for its nighttime views--but with the Aqua-Line tunnel
from Kawasaki flooded, they're forced to take a huge detour all the way
to Kisarazu! On the way, the two swing by Akihabara to investigate a
mysterious radio signal. Could someone still be alive there...?