The Night is Soft

In a quiet rural village, there is a place where laughter never fades, from children to white-haired elders alike. It is a small piano academy run by the village’s young headman. For reasons no one quite understands, a hollow-eyed man whom the headman calls his spouse teaches all the students alone, a one-man labor operation.
But beneath this peaceful everyday scene lies a chilling twist. Once the academy closes and night falls deep, the headman and the academy director begin taking out various murder weapons, one by one, from a secret storage room hidden inside the school.
A gang boss who abandoned his organization and went on the run, and the undercover police officer assigned to keep watch over him. That is their true identity, one the villagers know nothing about.