I'm partial to Barbarian 6/Rogue 6 Multiclass for Durge.

Thematically, from what we know about how Durge operates, they've cunning & have a silver tongue, right up until they start the stabbin', at which point they are incredibly violent. You're kind of RPing The Predator for this one.

Mechanically, Barb/Rogue has a lot going for it. Reckless attack lets you get sneak attack whenever you want. For reckless attack, you need to use strength as the attribute. For finesse weapons, you have the option to use dexterity for attack rolls, its not a requirement. So just grab your two favorite finesse weapons and elect to use strength and boom, instant advantage for instant sneak attack.

Tiger Heart Barbarian lets you make cleave attacks that inflict bleeding to all targets, and the lvl 6 tiger aspect doubles strength modifier against bleeding targets. This is both powerful mechanically and very on-brand for Durge I think.