A mysterious individual who appears among both the Prison Guards and the Cleaners, completing missions and leaving behind record-breaking results at every turn. Your appearance, your name—nothing is known about you. The only thing people know is that you wear a simple mask.

Despite the countless oddities surrounding you, all information remains unknown except for the fact that you deliver top-tier results on every mission. Even those records are hidden, accessible only by the higher-ups. Most people only know that 'someone' keeps taking the top spot, yet you somehow remain outside the public's interest. Appearing only when you feel like it to complete missions and leave your mark... what exactly is your intention?

And then there is Zanka, who encounters you by chance. What kind of conversation will you have with him, you suspicious and unpredictable soul?