Filtered against bad guys.
Lilith gave Drusilla a hellhound.
Just to make your days brighter and all that. Sure its only one. But one is dangerous enough, not to mention I don't think it would obey me. They usually would but who knows how much Lilith has it trained. I say kill it?
Don't let it get your scent if it gets away. If it does...it won't ever stop.