Mr Pudding ghost specifically licked the holy bracelet and called it bitter... and then said the tentacles were bitter. Maybe the tentacle ghost is some kind of holy thing?
Yeah I've been wondering about the strength of pure spirits.
Ah, I just remembered. That chapter where the kid lost his amulet in the river. The pure spirits following him was able to subdue a strong looking river spirit a little, just by pointing at it. IIRC the river spirit didn't even try to touch him.
Seems like they are strong but not in the way an ugly spirit can be strong.