Are these evocii?
What is the species carrying the Hutt in this picture?
Well, maybe not carrying it...
Evocii, I think.
Yes. They are Evocii.
slaves
Yes, they are Evocii.
If you want to experience Evocii "for real", play the bounty hunter or imperial agent storyline in Star Wars: The Old Republic.
You can play it as free to play, since the Evocii are mostly just on the starter planet (Nal Hutta) for those two classes.
IIRC there's one or two Evocii on Nar Shaddaa too, but you don't interact with them (unlike on Nal Hutta).
I found myself both sympathizing with them and hating them at the same time.