I bought this in Taiwan so the text is in Traditional Chinese. This 400-page "encyclopedia" was probably the best purchase I made this summer (Newtype magazines are 3 times the price).
Other than the typical Character Info and the reviews on what has happened up to the eleventh volume. It also contains information on interesting phrases and objects that come up throughout.
Most the info is text-based and about 1/2 of it is stuff we already know presented in a different manner.
However, this section would probably wow people even if language was a barrier: KJ's early designs of SR Characters



Most of the important information, translated
Pg 390,391:
Harima wasn't originally named "Harima Kenji" but rather, 京極誠.
On the picture that features Harima and Karasuma, there's a girl that is never featured...
When the Motorbike scene was drawn, Harima was not yet the main character. (It was Nara, right?)
Pg 392,393:
Tenma's original character setting was "normal high school girl" but when KJ decided to add her characteristical ahoge, that all changes. In the first stage, she looks much wiser... uncanny.
Pg 394,395:
The "Kai" version of Yakumo was made to portray the "girl that hides her emotions" character setting.
Eri was originally designed with a different hair style, looking a little more gentle and caring. (cute...)
Pg 396,397
Hanai had curly hair! but Mikoto looked pretty much the same.
Sarah's hair was not tied up in a bun.
And, Takano Akira, with Long Hair (Godliness, I love long hair

)
over.
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