you *could* also make it an environmental effect.
Lots more tracking and dice rolling this way.
make them resist a difficulty at intervals. Crank up the difficulty gradually the longer they stay.
Or,
have everyone roll against a single attack right before they leave to represent their exposure.
Base the attack on the NPC vamps skill as if they attacked with addictive saliva. Add an aspect (or tag the scene aspect) if they are there longer to represent a bigger exposure to the narcotic.
The last way to do it would be to use the rules under 'Addictive Saliva'.
Typically, however, this saliva is administered
out of combat—usually with an act of
intimacy (kissing) or unintentional ingestion
(spiking the punch). Roll Deceit with
a +2 bonus against the victim’s Discipline.
This is considered a “consequential contest”
(see page 193); if you win, you inflict a relevant
consequence (usually Addicted) on the
victim, severity determined by the contest.
I think this would be the best way of doing it. Really, it's the same as owning a bar and having all the drinks spiked.
The severity would be mild at first but would, probably, increase the more often someone visits.
