Merit's Aku Research
So, the first thing that is an issue, is that there are lots of hints that Aku is the name (or part of the name) of the Great Spider Spirit. That pretty much swamps everything else, like trying to do a background check on a random accountant that the only thing you know about is that he's named Robert Redford.
You do pick up some other small snippets:
- A cautionary tale, the sort of thing you would tell to your children to teach them a lesson, about "Aku, who was not satisfied". There are various bits where Aku has something perfectly reasonable and is not satisfied, and does something foolish and over-the-top in consequence. Some examples are eating a pot of soup, and then eating the hot coals when he is still hungry; building his house on a hill, then on an extra-high hill, then at the top of a tree, which falls over.
- There's also a small set of stories you find that refer to the Hungry Darkness. More like a vacuum in modern terms, Aku is thought to be where other things are not. Perhaps this is why he's never satisfied. Unlike his kin, who merely resides in Shadow, Aku actually resides in (or is?) the Darkness that is Empty.
- A final story about a conclave of demons, in which a number of particularly wicked demons make plans to storm/conquer/attack the World Above. As is often the case in gatherings of villains, each demon has its own favored method and tactic, and they tend to clash more than they work together. There is a demon of bleak cold and a demon of hunger and a demon of razor wind and a demon of too much sake (who talks to much) and a snail-headed demon, and there are a couple of mentions of Aku, who suggests the attack be made at night when there is no moon and no stars, "but his words were too dark and no one heard them."
After piecing those things together, you get a definite sense that a lot of this stuff has been eliminated from the record. You probably would have missed at least two of the above if not for your massive roll, and even those things you have seem more like overlooked scraps rather than real references.