tbh i'd want to be Starscream's pet rather than Megatron's because i have the feeling Starscream would go to great lengths to make sure his pet looks their best and is comfortable. miserable pets make for miserable owners, you know. shit i want to write this now.
honestly, both starscream and megatron would make sure their pet would look their best (as well as knockout, for obvious reasons).
being comfortable, however, is a completely different story. it all depends on how much the cons actually /care/ about their human. It’s different scenarios, and depends on if we’re thinking about what would actually happen, and what would happen if said Con was infatuated/possibly obsessed with the human pet in question.
First, let’s look at what would /actually/ happen.
If Megatron and Starscream only kept the human around to literally /be/ a pet, and a trophy (possibly to show off to the autobots), all they’d care about is keeping said pet looking somewhat presentable. Comfort and happiness aren’t top priority.
Under Megatron’s ownership, the human would be taken care of by other people, for the most part. Various Drones, Knockout, and Soundwave, to name a few. You’d most likely get fed, and groomed by said medic, but not much else. And then, the only reason Knockout even cares to groom you is that he wants to kiss up to Megatron- and what better way than to make his pet look pretty?
Starscream’s a different story. The con’s too prideful to actually ask for assistance from anyone else aside from, possibly, a few drones. You’ve already lost your best bet for any kind of good food (Soundwave) and meticulous grooming (Knockout). Starscream would give you the necessary materials to groom yourself, but would- most likely- refuse to even touch you. Cold baths and disgusting bathroom areas are sure to happen. You may get your cage clean once or twice a month by Drones. But let’s face it- they care about you even less than Starscream does.
Next, let’s talk about scenario B- obsession and infatuation.
Megatron would only have two trusted people look after you, if he couldn’t. Knockout, and Soundwave. You’d get treated well, but Megatron would still be an overbearing presence. Overbearing to the point you’re smothered, and can’t do anything without him around. As you’d expect, he’d make you rely on him for /everything/. Most likely: Stockholm Syndrome times seven.
Starscream, as before, is too prideful to ask for assistance from anyone. This time, the Drones are /only/ involved to clean your cage. Starscream is no stranger to grooming, and he would make you look very pleasing. He’d carry you around- most likely to just show you off, and then get enraged if anyone even /seemed/ to show interest (same with Megatron, to be truthful). Just like Megatron, he’d make you rely on him for everything.
Both of them would bring you anything you wanted, but only to make it seem like you didn’t need to leave. You have everything you could ever want with them- why would you need to go back to your boring life where security wasn’t a certainty?
Sorry this got long, I just…. /really/ love the good and the bad to this idea.