(art here by Brian Bolland, usually Zirk was drawn by Steve Dillon).
So. Zirk is this alien who really IS alien. Flying around on his mentally controlled platform,
he engages though in various unsavory illegal activities like smuggling. Mostly, he's a complete pervert who is aroused by anything with long appendages, paricularly if they wiggle. Human women appeal to him, but he'll also do it with anything from nightsquid to the severed neck of an ostrich. It's not clear what goes on here, since he apparently has no external organs (not even eyes or mouth). Maybe he does everything telepathically, stimulating his victims' pleasure centers. Or maybe he has inverted organs which emerge at the proper time. It's best not to know, but we should notice that Zirk's partners/victims becomes immensely infatuated with him. ("Love 'em and leave 'em," he smirks.)