Just based on the general vibe of the game, I wouldn't expect a route where Yui is saved or gets retribution. It's supposed to be a terrible dystopian future. Heck, you start the game by trying to kill yourself after completing your "Bucket List." Maybe I'm a sick bastard by I think you should just enjoy the despair. If she gets saved, It ruins the vision. Though, It would be cool if after hitting the next quota for the store, you find out that Yui has been thrown out of the store for some reason, and then you can take her home as the "defect" she claims to be.
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Maybe but, we don't have to be the one who saves her, maybe Dr. hel can. He foster "defectives" android, and in a way he could buy her to give it to another person whos just like us, and this wont even break story since when ever you do an experiment, like how Dr. Hel is doing, we need a bigger sample size. I have a rough idea on how u can implement this but we also dont know what the author have in mind.