Human centipede.
The artist (notfromthisworld) called those containers "tubes" himself.
About 400 images in the series and I will post some more.
That guy was so much underappreciated, when initially posting this
awesome series. He deserves a bit of praise.
I'll only post those, with actual scat in the picture.
The violet stuff is supposed to be that. Alien processing plant and all that...
This one is the very first with expulsion / scat in the series.