A bell ring is the signal
I don’t know what the sentence is but I would say Satisfactory
In "The feather pillow" by Horacio Quiroga when the parasites don't have a human to feed on they usually are small, they are parasites of feathered creatures. This parasite, in particular, has been feeding on Alicia's blood, that is why it became so monstrous. We learn about this in the last parragraph of the story.