Are the any other games, besides Teaching Feeling obviously, that have you buy/save/find/etc. a slave which you can then either train or help?
I know of
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, but that's pretty much the only one I can find and that one is annoyingly grindy after the introduction.
I was going to bring up Inheritance, buy you must've edited that in right when I clicked Reply. Not sure how far you got, but interestingly enough there are several hints scattered around that imply it's set in the same universe as Teaching Feeling, and that the uncle who you inherit the mansion from is the one who tortured and scarred her.
I don't think I like that, I don't find Inheritance particularly well written. I don't know if they're affiliated with freakily charming or not, I doubt it having not looked into the subject at all, but it kinda feels like they're just trying to piggy-back off of Teaching Feeling's popularity a bit.
Let's see...
I want to say there's tons of stuff like that out there, but I'm having a hard time thinking up specific examples. If you don't mind reading, and not having art, there's CoC and TiTs. Specifically, there's a giant fairy some goblins kidnapped in CoC, and The demon trader on the first world in TiTs. The former doesn't really live with you and isn't a huge focus.
You are the one to enslave the latter, so I'm not sure if that counts, but you can train her up to be somewhat affectionate, or a broken slave.
In that vein, and since it's been on the front page of recent updates recently, there's Fall of Eden. There's an interaction with a fox-thief in one of the questlines. Again, you're pretty much responsible for enslaving them, and I'm not sure the relationship is totally finished, but you can get them to be affectionate, from a resentful, rebellious slave. There's actually a few characters like that.
Aside from that, most of the trainer games are basically that. Akabar's witch and princess trainers, and the four elements trainer, which I would go for first.
Those are probably prevalent enough that you've heard of them, but technically they do fit into what you're asking for. I'm sure there's plenty of others, if you look.
Then there's
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an amazing series where you play an ex-hero contracted to defend a dungeon for a demonic overlord. Aside from the porn, it's a (somewhat difficult at first) dungeon-crawler with really good gameplay. It's very non-con, but it's weirdly vanilla non-con, if that makes sense, where most of the characters end up liking it and loving you.
One of the main relationships involves a fellow adventurer, who is your first prize. She's forced to live with you, and starts out hating you, but you gradually form a connection with her. Again, you're
kinda the one enslaving her, and there's not much you can do to directly interact with her here, aside from progressing the story, but I feel like that would satisfy at least some of what you're looking for.