My interpretation is that the site was basically ancient people using multiple levels of security to contain a fucked up thing.
Like the bottom layer (actually there could be even more shit underneath) has human sacrifices, which might be sorta powering the dogu on the upper layer to make them more interesting to the god in the center, and then it's all held together by evil slough (discarded hair) that they maybe got the fucked up thing to go into a bit?
Overall effect: fucked up thing is contained as long as no one touches anything
Whole chapter makes me wonder what archaeology would be like in a world where ghosts and shit were super duper real.
Like on the one hand a lot of the academic aspects would be difficult/impossible because you couldn't just dig shit up willy nilly, but on the other hand there'd be a lot of times where they'd need someone to defuse something harmful or restore something broken.
