There’s a lot of research involved in any historical piece. I heard Susan Spann, author of Claws of the Cat, say that she had spent over two hours looking up historic ikebana seasonal arrangements, just to put the correct flowers (hydrangeas) in a scene. I myself spent considerable time researching the histories of such commonplace things as daikon and goldfish. But sometimes the source material is hard to come by, especially in English.
There’s not a lot of good English-language material on onmyoudou. What can be found must be vetted carefully; I found one of my handiest references actually contained a considerable transliteration error (chokuban as shikiban), for example. Some sources are available but only within certain academic circles, and I didn’t qualify.
There is more material available online in Japanese, of course, but I speak only enough Japanese to get myself in terrible trouble, and I don’t read more than a few characters. So I tried a handy online translator. Occasionally it was useful, but at other times…. Well, just let me share a few gems with you.
You might remember Abe no Seimei, a real-life Heian-era onmyouji who has been elevated to mythic status (rather like the western Arthur and Merlin). Today he has an asteroid named after him, he’s the subject of several period fantasy films, and he is mentioned in both Kitsune-Tsuki and Kitsune-Mochi. The photos in this post are of a shrine dedicated to him.
You might be slightly less familiar with his seminal work on the art, Occupied Thing Abbreviation Decision. (His book Senji Ryakketsu is called by less colorful translators The Summary to Judgments of Divination. My best guess is that “occupied thing” refers to a shikigami, a spirit within a physical construct, but that’s the best I can do.)
“Purple fine Doo number” is of course a very important piece of fortune-telling. The trout weighing makes it more accurate.
This is from a step-by-step process for scrying in onmyoudou. If followed correctly, it is possibly to predict finely fortune elephant meaning.
I did take a bit of artistic license in my depiction of onmyoudou, mostly to provide some sort of visual context and reference for purely spiritual and invisible activities, but I tried to keep an authentic tone for most of it. But I do apologize for any unintentional errors which may have crept in as I was working with my resources. At least I avoided the trout weighing and finely fortune elephant meaning.