I wish I had more to give you, anon! most of my theories/headcanons about akira are just that—we don't have a lot. we do know that they have people they want to return to back home, but they also seemed to have lived a rather lonely life—this is not just inferred in their comfort in a community of cats, rather than mentioning specific people or those who made an impact on them (though this would be an obstacle for anyone looking to project onto akira, so I don't pay it too much mind), but that they also seem to consider the eastern country most like their own home in tokyo. the kind of foreboding, impersonal loneliness that the eastern country fosters is familiar to them.

realistically, they were probably a regular office worker, but my personal theory is that akira was a teacher! in particular a teacher for younger children, at least somewhat disillusioned with their field. they have an incredible knack for interpersonal problem-solving, especially with riquet and even more so with mithra, that I think really speaks to experience with children—you'll notice that rutile often does a similar thing! rutile and akira's outlooks on working together are also pretty similar, and those shared values might have led to convergent careers (shrugs)

the disillusionment comes from the fact they never really mention their job—obviously, this is also something that could alienate readers who want to project, so it's not something to take too seriously, but I feel like most stories in this same situation wouldn't hesitate to mention something like an office job. that's going to be the circumstance of a majority of their players, probably, but mahoyaku is also special in that regard—I think it takes great care in its storytelling in considering what kind of people play their game. iirc, it was one of the first joseimukes that allowed use of a protagonist of each gender, and the writers have spoken before about crafting a story that doesn't become outdated. leaving akira's job nebulous leaves open the opportunity for people who are alienated by characters who do more "professional work" to more thoroughly enjoy the story.

really, though, I think akira's strongest characterization is in how they handle their own personal conflicts. central etude, the second part of the main story, and anni4 (as examples) put akira in a lot of positions of conflict and strife, where they struggle over what to believe. it's those decisions that rely flesh out akira as someone "human," someone who makes mistakes and struggles and does their best to really reach those they care about. it's especially effective because akira pretty readily admits their own flaws when they think they're wrong—anni4 was particularly impressive here. a character who can't admit when they're wrong is bound to feel unreliable and dishonest to a reader, but akira is quite straightforward and honest with themselves.