Oliver & Company (film)/WMG

Desoto and Roscoe are actually hellhounds.
Sykes bought them at a demonic petshop in Hell, and used them to threaten or even kill his (Sykes's) victims.

Each doberman pinscher represents a different sin: Roscoe, the sin of Lust and Envy, and Desoto the sin of Greed and Murder.