One interesting oddity about the Japanese is their odd compulsion with blood types, and I remember reading Saint Seiya manga back in the 80s and wondering why the comic went out of its way to list the blood types for all the characters. The answer, of course, is that the Japanese somehow came to believe that a person’s blood type provides a lot of information about their personality, etc. Type A people are neat, tidy, and plan things meticulously, almost to a fault (my wife). Type B are “my pace” (as the Japanese say), meaning that they do their own thing without worrying about the opinions of others, and don’t plan things out in advance (me). Type O people have a private world inside their minds, supposedly, and they’re quick to become passionate about something, but then change to something else just as easily. Type O make the best leaders, it’s thought, and during WWII the Japanese government went out of its way to recruit soldiers with type O blood. Finally, AB people have “two faces,” one that they make in front of some people and another one they keep to themselves. Depending on where you’re from, there’s a good chance that you don’t know your own blood type, and this is something that shocks Japanese people, who are as familiar with their own blood types as they are with their shoe sizes.
The Japanese are big on Blood Types.