The bits and pieces of weirdness are starting to seep through the cracks more with each episode of Ookamikakushi.
This disease (for lack of a better word) that Issei and others in the village seem to have is at the forefront of everything at the moment. In just about every situation we have seen the telltale symptoms of whatever this is (most notably the glowing red eyes), the character in question was close to getting his or her freak on, or perhaps just really horny. But I don’t think sexual excitement is the stimulus for the symptoms; rather, it seems pretty clear that it is the reverse — the disease itself causes a raging case of boner.