This is a Japanese (or English) language manga (comic) or a magazine featuring multiple manga series.
Using work done for "Samurai Champloo" and "Ergo Proxy" as examples, this softcover book demonstrates the process of establishing a character's look, stance, costuming, etc. Quite a bit of text (all in Japanese), but profusely illustrated with animation drawings, cleanups, rough drafts and finished work. A fascinating glimpse into the creative process!