The Sea of the Moon, the seabed.
More precisely, somewhere below the seabed... far below it.
It was utterly dark here. Despite being amid layers of rock and soil, faint sounds of writhing could be heard.
They sounded a little like stone scraping against soil, yet also a little like flesh squirming.
No one knew what lay beneath the seabed of the Sea of the Moon. No human had ever even set foot near the seabed.
Yet a Spirit Body drifted up and down here.
Elsa's Spirit Body obeyed Elliot's commands, but she had no ability to think for herself, and even her execution of orders was extremely rigid.
That was why Elliot had given her extremely detailed instructions.
As Elliot saw it, Elsa's Spirit Body had followed him all the way up, so she should know the route, and the Dream Creatures might also help.
Thus, his instructions were: [After sinking to the bottom, search nearby for a passage and enter it. If none is found, return the way you came.]
Throughout this process, Elsa could automatically absorb light spots from Dream Creatures. Elliot's original intention was simply to send her down to see whether she could absorb the rocks.
Even if she could not find a passage, absorbing some rocks to advance her Resurrection would still be good.
So, in addition to that command, Elliot had given her one more:
[If you encounter large quantities of absorbable entities before returning, stop where you are and absorb them.]
He had made all the preparations, specifically leaving Elsa's other corpse at the passage entrance. As long as her Spirit Body appeared nearby, he could immediately regain control.
That should have left no issues with the logic governing the entire operation.
As for whether absorbing those [Flesh Chunks] posed any risks...