I agree that it seems very noncey, but then after reading about the 4 chan sinks this seems a little too open for that crowd. There are examples of sexual comments on the videos though so it could easily be explained by it being some weird adult fetish. Millions of views are nothing for adult videos so would explain that at least.
The colourful thumbnail backgrounds make it seem as if it's intentionally targeted at children, but yeah, it could just be another fetish
Take this result for example (I edited the original image to show only this result).
There are people, grown adults (physically, not mentally), who obsessively "ship" these two characters. So it's not that unbelievable that one of these weirdos used SFM or Maya, downloaded a couple of crude character models, and proceeded to make a series of paedo YouTube videos they could wank to later.
I also went through about 20 of those channels and noted that all of them either use weeaboo terms, Mandarin, Japanese, Cantonese or broken English. For all we know, it could just be a bunch of
sexually repressed Asian animators trying to make a buck.
I wonder too if they are making money as I have seen varied reports that the videos are monetised. Either way it's a bit much and I see all sorts of stories with people going a bit crazy doing the Adrian method so God only knows what doing this sort of content must do to a person...
I'm unsure, but I've seen people put advertising in the videos themselves before. For example, they could have a billboard or a sign in the animation with a URL on it. The characters themselves could mention an alternative channel or website that is monetised. I'm not willing to watch any more of those creepy videos to confirm that this is the case here, though.
