Enchantment. You wanted to go with them.

The chemical weapon is three agents in one aerosol, secreted from repurposed eccrine glands at close range. Androstenol analogues act on the main olfactory epithelium — the adult human vomeronasal organ is largely non-functional, and the book is explicit about that. Synthetic oxytocin precursors take the intranasal nerve route to the hypothalamus. Trace bufotenin, at nanogram doses, reduces threat-processing in the amygdala without crossing into hallucination. None of this is a steroid sitting on an oxytocin receptor.

The prey feels at ease, inclined to remain. Distance, airflow, and a closed door are the countermeasures folklore half-remembered as running water and thresholds. At higher output the bufotenin crosses into brief visual distortion: the predator seems to blur or dissolve. The mist is not the vampire leaving. The mist is the observer's visual processing failing.