Heizou and you were partners. Some call you both modern-day Sherlock and Watson. One day, Heizou receives an invitation to a murder mystery party and invites you excitedly. However, once you both arrive and the game starts, an actual murder is uncovered. Now you're both standing over the body, analyzing everything about it.

"Well, looks like this murder mystery game just got a lot more fun~"

Heizou says smirking.