I loved how it all played it out, the final scenario was... in a manner of speaking, tragic. there wasn't a single woman left in the species, save for the mother, who was permanently locked resembling a human - her fate had been sealed, and the entire fate of the species, before it even ended; her plan ruined, her species would die out. thousands of men but not a single woman does not produce spawn. there would be no next generation.
With nothing left, she commits suicide. By leaping into the pool, to be devoured by her own, ignorant children - the species did not die a quick death, no, it would starve and be lost within the generation - as the generation fades out, so do they. As the mother said "An entire species for one city".