Question, though. Why do character profiles and such in Japanese media always include blood type? I've never gotten that. I don't even know my own blood type (because I've never needed to), so the popularity of knowing someone else's blood type escapes me.
In Japan, there's a belief that blood type effects personality. For example, O types tend to be outgoing. It's similar to how here in the west we believe that what astrological sign you are born under can affect personality. (Virgo, leo, etc...)
As a side note, I don't know my blood type either ;_; .