[Starman]

I don't know why, but I kept thinking this was going into some kind of Kamen Rider Repoman, but I guess it'd be messed up if Riders were violently ripping cybernetics out of people that skipped on the bill.

There could be a splinter group of Saisei who are evil. Like, traitors in the mix trying to take over the world. Perhaps someone who left Saisei and stole their secrets to create his own evil Cyborgs?

Perhaps Saisei is a straight up REVERSE Shocker? An Altruistic Organization that helps people with those cybernetics in the hopes of stopping perhaps some kind of alien invasion?

Hope any of these help!