parasitic

adj

1. Of or pertaining to a biological or symbolic parasite.
2. Drawing upon another organism for sustenance.
3. Exploiting another for personal gain.

   “While some companies seem largely indifferent to gold farming, others see gold farmers as unfairly extracting value from property that they do not own. Gold farming is often described as a parasitic business practice that undermines the stability of virtual economics.”

4. Of emotional damages: accompanying a physical or pecuniary injury.

noun

1. A component of a circuit that does not show up in a circuit's schematic but does show up in the circuit's behavior.