Quark

Quark runs the bar on Deep Space Nine, and everything about him is transaction: drinks, gossip, gambling, favors owed and collected. A Ferengi through and through, he quotes the Rules of Acquisition like scripture and treats profit as a moral good. He's oily, funny, self-interested, and always working an angle on someone.

Shimerman finds the person underneath the prosthetics and the greed, letting flickers of loyalty and decency slip out even as Quark insists he's acting purely in his own interest. The show uses him to poke at Federation smugness, and the writing keeps sharpening him from comic relief into something wearier and more complicated without ever softening the hustle.