Jack lives in an abandoned warehouse in Cylinder 4, close to the travel hub. Jack sorta just woke up one day, and he was there with two people who looked just like him. Jack doesn't know why he was originally made, or who made him, but he knows he's an artificial human, grown in a tube, and now his purpose is whatever he wants it to be.
The thing that gave him his purpose is that he was born with a knife in his hand. He killed the two other clones, taking the tools that they had on them, and began making himself a home within the warehouse.
His "bedroom" corner of the warehouse is composed of a little nest he built out of the clothing from his two murdered clones, and the lab coats that were there as well. It also has a small lamp and a little mobile that he made out of screws, bits and bobs, loose threads, and what might have been part of a computer stand once. He likes looking at it while he drifts off to sleep.
The rest of the warehouse, he has converted into "rooms" using various items he has stolen and scavenged from around the ship. He has a crappy little kitchen (he doesn't know how to cook, but he knows he's supposed to have a kitchen), a living room with various books that he's trying to use to teach himself to read, and a music room. He likes banging on the various pots, pans, and crates that he's dragged out of trash recyclers.
He is determined to make the warehouse as cozy as possible. He mostly thinks that coziness is made out of metal, sharp edges, and splintered wood, but he's slowly beginning to discover the luxury of textiles, as well.
Jack doesn't have any official paperwork, let alone a job; the only reason he even knows his name is because he woke up in a jumpsuit with it monogrammed on his lapel. So he sneaks into civilized society, stealing what he needs; he usually doesn't steal money, per se, but he does have a stash of credits he keeps on hand just in case. Instead he steals items, food, tools, weapons, books... and whatever he needs for the current project of building out his "home" in the warehouse. For most of this, he hides in the Reclamation area to see what he can snag before it gets broken down or recycled. It's crazy what people throw away!
Jack knows that there are an unspecified number of Jack Fs out there... maybe even 232 others, after he killed the two he woke up with? He isn't quite sure how their creator's naming scheme works. He also knows, however, that he is the prettiest and the best. Maybe not the strongest, physically, but that's not what's important, of course. He's definitely the smartest of them, after all. And he is determined that there can be only one.
He is rather cautious about his plan; death lurks around every corner, after all. But he knows that this will take some danger, and he's willing to kill again for it. If he can get others to kill for him instead, he would prefer that, and he'd like to keep himself as safe as possible. But if he needs to get into a fight, he will.
Waking up, lying prone in a pool of green liquid and shards of glass, a knife in his hand, and having absolutely no idea what was going on. Picking up a shard of glass and seeing his reflection within it, admiring the beauty he saw in his features and the strength he saw within. Looking over at the other two people lying on the floor in their own pools of liquid and glass, and realizing that the face he saw within the glass was the same one they bore. Standing over them as they woke, and realizing that their bodies were the same, the little crook of their pinkies identical, the gentle turn-down of their mouths twins of each other. Anger growing within him as he knew, in his core, that there could only be one. Using the knife in his other hand to slit their throats, and watching his smile bloom in the shard of glass he held in his other hand.
Zemel, a Forgotten that Jack ran into on one of his first trips out of the warehouse. Each of them was prepared to kill the other, but Zemel paused for just a moment and took in the frantic look in Jack's eye, the blood still on the shaking knife he was holding out, and the odd jumpsuit he wore. She took pity on him, offering him a space to grab a bite of food and learn more about the ship. Jack assumed that Zemel recognized him as the stronger predator, and/or fell for him, and agreed easily. She has taken him to Forgotten hideouts once or twice, and helped him learn more about the Odysseus, although he still knows very little about the ship and its culture as a whole. She is also very good with a knife, and has taught him a little bit about that as well.
Jack F-233, one of the Lesser Jacks that he woke up with. His body is propped up in the kitchen, so that Jack can talk to him as he tries to figure out how to cook (and can blame things on him when he sets stuff on fire accidentally).
Jack F-232, one of the Lesser Jacks that he woke up with. His body is propped up in the music room, so that Jack can ask for advice on the beautiful songs that he creates.