Tenra Bansho is a localized translation of a Japanese science-fantasy RPG. I have to say that I had to think very hard about buying this game for various reasons (I won't get into them here, but I've written about my reasoning at http://kawaiisaa.blogspot.com/2014/02/tenra-bansho-zero.html).
In any event, I did in fact decide to buy the pdf version of the game, and I think it was well worth the price. The two main parts are a b&w rulebook of ~450 pages, and a color worldbook of ~240 pages. I found the part in the Welcome section of the rulebook describing the difference between CRPGs and TTRPGs rather ironic given that at one time if you talked to other gamers about RPGs, they automatically assumed you were talking about TTRPGs.
TBZ is a type of storytelling game, which I frankly have no experience playing. A general overview of the system is given in the Welcome section, and explained things quite satisfactorily.
Character generation uses archetypes and attribute points that are distributed by the character. "Fates" are also selected for the character. These seem to be along the lines of Passions from Chaosium's Pendragon RPG, but seem to be much more important in making sure the character is involved in the progression of the story.
Actions are resolved based on making die rolls tied to a skill/attribute against a challenge rating or the rolls of another character/NPC, with the GM interpreting the outcome of success or failure.
The Character Rulebook section is devoted to the description and various rules specific to the archetypes that players can choose, including Armour (Yoroi) Pilot, Sorceror (Onmyoji), Samurai, Monk, Ninja (Shinobi), Illusionist (Kugutsu) etc., to the more exotic Annelidist, Oni, and Ayakashi. There is a lot of good information in this section which can be mined for inspiration even if you don't plan on using the rules.
The worldbook starts with a lavishly illustrated introduction at the beginning, followed by a short gazetteer and a historical timeline. Various social, cultural, political, and technological subjects are covered in this book, and I'll just leave it at that.
The pdfs are not mapped, which makes navigation more difficult than it needs to be, particularly for the lengthy rulebook. I also didn't care for the A-head font used in the text - the "H" and "K" look almost identical, so half the time I was misreading "skill" as "shill" and "kijin" as "hijin".