It's like a manga curse. I see so many good stories that are dragged beyond reason, start completely new plot after finishing the original premise. It's always ridiculous,forced and feels like characters behave like husks of their former selves. Just corporate greed, let a good stories end and write a new one don't just try to milk dead cow till the end of time.
I don't really feel like this one is a good example of this though. Like, yeah, it's probably went on for too long. It's not going anywhere story-wise. I kinda forced myself to catch up to the end just because I read far enough where it felt like it'd be silly not to.
But I also don't think it ever hit a point where it "finished" the original plot. I do see that from time to time, but the vagueness of this one kind of kept it from ever happening. There was never any original endgame. The entire thing is "ah, magic hotspot, let's see what happens".
So it was kind of fun for awhile, and eventually it just got a bit tired. It's almost worst that way. At least the stories that wrap up and then continue anyway can more or less be dropped at a decent conclusion. With one like this, you just kind of have to choose a point to jump off the train, there are no meaningful stopping points.
Anyway, that's my 2 cents on this manga. I probably won't be back here to read it next time it updates. It was good enough to kill some time with and I appreciate having something that's further in than 20 chapters even if it's not amazing, but I've got my fill of it now.