Reputation: 27Actually, many anime artists try to differentiate the eyes of characters that are ment to be of other nationalities.
They ussually portray Japanese eyes with a slight box-like approach while (for example) American (or caucasion in general) eyes would have a more round shape.
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Side note: That picture posted from Black Lagoon, funnily enough, most of the characters in it are supposed to represent many nations other than Japan. Apparently, you figure out near the end of the second season that all of the characters involved with the Black Lagoon transport company are supposed to be speacking English. (This becomes obvious when suddenly the gy is translating from Japanese to .. Japanese? That and some of the characters start curseing in English (a very bad dialect))