My gut reaction to the denouement of this chapter was "The inner machinations of the mangaka is an enigma."
How did things go from being assaulted by whatever that monster was, to the long lost friend being recaptured and sucked through a wormhole, then back to ambiguous onee/shota?
I think I'm a bit baffled, too, because this is possibly the first time a design in this manga forced me try to figure out where I could even look.