whats the word that describes a person who encourages someone with an addiction to have more drugs or alcohol?

Question by san: whats the word that describes a person who encourages someone with an addiction to have more drugs or alcohol?
its one of those things that i know but cant for the life of me recall right now.. its a provider or instigator, something like that. people in 12 step programs are asked to stay away from people like this.

Best answer:

Answer by Warren
bastard

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