
I was also thinking about how I'd like the story to end. In Killing Stalking, I want to see Bum save and Sangwo either dead or imprisoned. But it's different from this manga even though the setting (rather, atmosphere) is kinda similar.
In KS, Bum may have already been a creepy dude (stalking and stuff), but he was never really dangerous (until he killed someone, that is ^^').
But in Warehouse, the MC isn't someone innocent; he's probably hurt his kidnapper deeply, and he's not solely a victim just because he can't remember. I'm not saying that - whatever the MC has done to him - makes his crimes right, but if what happened before was really bad, I could totally see myself pitying the kidnapper for going insane because of the past.
And if that would be the case, I could actually imagine a 'happy ending' where they both end up together. And it still wouldn't seem like a cliché 'from-rape-to-love' story, but a twisted, fucked-up 'love' where neither of them could ever be sure of the other's true feelings. They'd probably depend on each other because they're the only people left who understand them; who can console them and lick their wounds; where one is just as mental as the other. And this wouldn't be considered a 'happy ending' even though they'd have ended up together.
Yup, I think I'd like that.

Looking at his body language this chapter, I think Sungho is already far, far beyond Lima Syndrome.

Lima Syndrome? No, I think the MC's attitude doesn't match for that. Same for Stockholm. The MC wants out, feels hatred for scar face, and is doing everything he can to fool the guy to set him free. Well, right now he's not. Whose to say what will happen when he remembers. He could fall into one of those two syndromes.
It would be kind of sad, though, don't you think? A happy ending because you were brainwashed into falling in love with your captor...
I honestly can say that I cannot see any kind of happy ending happening in this story. And, if by some miracle the author does end this story with a HEA (Happily ever after), I think I'd be a bit disappointed.
In most yaoi that begins with rape, it's mostly an eye-roll away from them falling madly in love. I think this story is too good for it to end like that. I can only hope that whatever memories scar face is trying to make the main character remember, will leave the both of them with some kind of closure.
Or the main character escaping after killing his rapist, either way, no falling madly in love, please!