Mann & Machine - Spy

Backstory

Spy was created in a lab via a lot of science and genetic engineering in order to be good at spying. Sort of like Agent 47 from Hitman, but with more emphasis on being made of nanomachines that allow you some degree of shapeshifting. Well trained but chafing at the restrictions that came with essentially being property of an underground crime ring, Spy eventually broke out and ran away to find a better life somewhere else, taking on the name Marin as he did so. Only for himself, of course - he changed his identity as often as was necessary, and hell-bent on staying under the radar as he was, that was quite regularly.

After a few years fluttering around doing odd shifty jobs, he eventually met a woman in Boston. For a short while, he genuinely considered dropping out of the business altogether to settle down. It was an idyllic life he had never really thought about, and though he very much enjoyed the fancy things his recent work had gotten him, the idea sounded like a good one.

And then his son came along, and the illusion broke. Marin hadn't thought he could have kids, and the possibility of a child who would be just as much of a potential asset as himself - no. He couldn't afford to stay, he couldn't afford to get attached. Think of greener pastures, leave and don't look back.

So that's what he did.

Notes

So, I put a lot of thought into Spy and his whole ditching situation. In terms of the actual qualification of it, and making judgements, I think it's probably more important for the reader to make their own decisions, but there's a couple of things that I do think are fairly certain. For one thing, I think it's a very important part of Spy's personality that he refuses to back down from his choices no matter what. I imagine that's a sort of continuation from his past, where he didn't really have that sort of responsibility for his own actions. So there's a certain degree of dissonance when he starts working independently, because he doesn't think of himself as fully in control of his actions (even though he'd never consciously say such a thing) which prevents him from really reflecting on himself. And this puts a stopper on some of his ability to grow and learn, I think, because he's generally more interested in maintaining this image of himself than he is in actually forming an accurate image of himself. It's his brand of cowardice, I suppose. Not to say that he is incapable of personal growth, because that's definitely something that he's done over time - but he's unable to properly kickstart it and very touchy about criticism, which slows him down a lot and puts a sledgehammer through his relationship with his son.
Furthermore, since Spy is one of the characters with a better grasp on what Mann & Machine actually means, he's very used to pretending to ignore or miss information, because that keeps him safe. And this bleeds into his real life a little, since he's forever playing at masks and such; to a certain extent, he is genuinely willing to ignore things that are right in front of him if he thinks it'll benefit him. So, while he's by no means clueless, his actual ability to put the clues together can be patchy depending on if he's having a day when he's more willing to be himself, or one where he's trying to be someone else.
Spy's two strongest instincts are to either fall into a role and blank out everything unnecessary until further notice, or to attempt to make himself as scarce as possible to everyone he knows. Not only does this make him very difficult to work with if something sets him off, but it also has the side-effect of scrambling his emotions a lot, since he's either actively repressing them or acting like a skittish animal. He severely overvalues the efficacy of both of these techniques, leading to him falling into a general state of exhaustion after coming off them, and also meaning that he consistently makes the same mis-steps in his personal life; steps that are exceedingly in character, but disappointing to those around him nevertheless.

Mechanical Description

His body is primarily composed of biosynthetic nanomachines, with some viscera and blood in between. This causes his form to be fluid, often "melting" in response to injury or reshaping itself as he finds convenient.

The nanobots that compose the bulk of his physical form are quite reliant on Australium to function. His respawn chip is, as with all the mercs, located within the interventricular septum. He could move it, but he's not sure he knows quite enough about that flavour of biotech to risk it.