Someone who is usually one part emo, many times one part nerd, and definitely has an extreme obsession with the country of Japan. If one of their group dies off they all get depressed and make themselves feel better by arguing that Japan is superior to all other countries, or they contemplate mass suicide.
bieng japaned is when you say something is going wrong with your life and somebody says, "you think that's bad? Imagine what it's like for the people in japan?" totally discounting that you could have any problems while the people of japan are suffering.
similar to not being hungry and then being reminded of the starving kids in ethiopia.
you: oh man, i shut my hand in the car door! it hurts!
them: You think that's bad? cars were landing on people in japan.