I do tend to write characters who'd be in the background if they ever occurred in the canon story (which in the FF7 canon, they don't) - I figure there's a lot going on in a big company like Shinra, and not all of it is going to get screen time. After all, there have to be a couple of people making certain of things like connecting houses to the power supply, sorting out billing, doing the day-to-day stuff. Hojo's "create biological havoc" budget has to come from somewhere - and this means there's a large number of people like Nesa, working away in jobs which aren't glamorous, aren't particularly rewarding, and often aren't the things they've trained for. The bills have to be paid, the rent is due, and the landlord isn't listening to excuses.
Nesa's honesty with herself comes in part from her training - she's a trained psychologist, specialising in abnormal psychology - and in part because she's not a human living in a Western cultural/social matrix. I figure the attitudes toward same-sex pairings on Gaia would be completely different to those here on Earth, if only because the Gaians haven't had Christianity screwing with their heads on a cultural basis for two thousand years. So to my mind, there wouldn't be the same sort of cultural tangle between sex and sin; as a result, there's more sexual honesty in my vision of Gaia.