You activate the hatch's controls while looking out with the camera: Still nothing outside.
The hatch's doors open sideways and reveal the empty corridor. A thing catches your eye on the adjacent panel.

Is that... Paper?
You take it off the wall and take a closer look at the hand-sized sheet. A single line is printed on it:
"カツロウに行く@ホウンガン"
Your muse quickly runs the writing through a translation software and reads out the translation:
"Go to Katsurou @ Houngan"

A quick check on the mesh reveals that this is most likely referring to Kyoshi Katsurou, the head researcher of the Houngan.