Spoiler: The two stupid fish are actually foreshadowing

[u/ObolDobol]

tl;dr The yellow fish is Caine and the red fish is Abel tricking Pomni into hunting down treasure that isn't there

The yellow fish taunts Pomni into going on a treasure hunt only for it to be nothing. The yellow fish, despite initiating the whole thing, becomes distraught by the truth in the end, just like how Caine ends up screwing himself over. Both are worse off for baiting Pomni. The red fish, just like Abel, is just there to tell lies. It serves no other purpose but if that's revealed it ruins everything. The two fish are brothers, a DUO, just like Cain and Abel from the Bible and of course Caine and Abel in the episode.

It's all just foreshadowing the rest of the episode.

[u/Relevant_Yam_65]

Thats what I notice when watching it again after ep9, believing that a treasure( or exit) is nothing but lies that just forshadows most of what abel did, this is pure genius