The floor groaned beneath the tatami as I entered. The room looked no more than 8 or 9 square meters, and the wooden box that dominated the space made it feel even smaller.

I edged closer and peered down into it. The light grain of the bottom was smooth and polished beneath the faint emerald light coming from the window. It was deeper than I expected, at least 60 centimeters, but narrow. My shoulders would just fit. I stepped back and regarded this, my bed for the night. There was no other possible interpretation: It was a coffin.