Despite looking like a normal enough human male (5' 11", blue eyes, short black hair), Gimlet is infact alien in origin. From what he has said in the past he was once VERY different in form and has genetically engineered himself to resemble humans.
Although he looks right, his body is very elastic, being able to survive falls from any height and probably almost any conceivable blunt trauma. This also allows him to swallow beings far larger than he is, so far at least twice his height with no obvious difficulty. He also heals quite quickly (usually a minute or so) and seems invulnerable to 'normal' acids. (Basically I don't like RPing digestion, just the swallowing bit.)
Normally Gimlet is pred, but an unusual one in that he doesn't eat for food, just pleasure (both for him and prey). For him vore equates strongly with sex and so he only eats females. He usually just holds them tight inside his safe second stomach, although on occasions he has, if the meal asks real nice, digested a nice willing female prey in his first stomach. His digestion just absorbs the meal directly into the stomach painlessly, no acids (Ick!)
Where ever a meal ends up Gimlet can if he wants distort space making his insides bigger than his outsides, hiding a meal inside him so nothing indicates he has fed.
As to his background Well, he's been on Earth for quite a while, and though he does seem to be a good geneticist he seems to prefer mechanical technology (although from what has been seen his organic 'tools' actually seem far superior to his mechanical ones). He also has a home he calls simply 'The House' that seems sentient... to a degree at least, and also seems rather powerfull, but seems to only follow Gimlet's directions. Perhaps it is more of an organic 'robot' than sentient