It's going to be somewhat dependent on how you do things. You can ghoul a mortal without blood bonding them by not having them drink from the vein. Ghouling isn't in and of itself a stain, but bonding is (V5 core pg. 240). And ghouls aren't slaves unless you blood bond them; you could have a positive relationship with the ghoul without the staining. It'd be somewhat hard to keep up with, but you could do so....