Alright, honestly this was poorly built up (non-existent build up) and bad execution.
It was fucked up, Boy's Abyss often has non-existent payoff or subverted expectations, but it leads to story progression and character development, and ties into the whole theme of the manga. It's never shit all over the story and buildup like this.
This manga had the potential to be better than Boy's Abyss but it failed in a single chapter.
This development should have been teased over the course of multiple chapters or even volumes, and then had a payoff, it was far too sudden like this. I'll stick around for a while, but I can't see it getting much better.