[Dark Wing]

Originally Posted by Guido

This is anime question:

Spoiler:

Towards the end of the fifth episode Satoru and Saki immediately realized the true nature of the viscous substance that emanated from the ceiling Satoru was poking with the spear.

I didn't get exactly what was that substance about?

There really any meaning to it it was actually just Satoru is just seeing thing as a result of breathing in some of the poison gas the wall were just caving in on them. You probably couldn't tell since the guest animation director of episode 5 did a poor job getting that across.