Nagahiro loses to Lai, but the Pretty Boy Detective Club figures out the trick that Lai used to win. In order to battle Lai again, they sneak into the Reasonable Doubt Casino. But at the moment of the showdown, the detectives are met with an unexpected situation! What will be the outcome of the battle between the rival middle schools?

The reason for Kodaki’s strange behavior remains unclear, but her family background and an “incident” that occurred in the past between her and the Pretty Boy Detective Club becomes apparent. Nagahiro finally decides to break his engagement with Kodaki. What will be the fate between the girl known as the devil and the Pretty Boy Detective Club?