Uniqueness in Japan

  Japanese teenagers are especially interested in blood types. They want to know [or: They like to know] what blood type their friends have, and many teenagers enjoy talking about blood types and character. So much so, that it has become commonplace for many of us to introduce ourselves by saying "My blood type is..." 
  A Few years ago, an interesting book titled "User's manual of own blood type" was published, and over five million copies of it were sold. Inside of the book there are [or: The book contains] check lists for one's blood type, and there are chapters about personality characteristics, and predictions of one's compatability with others. 
  I think that these types of cultural beliefs in Japan are nonsense.

Very interesting story Sakura, even if it is nonsense.

Uniqueness in Japan

We are interested in blood types, especially among teenagers.
They also know what blood type their friends have and sometimes enjoy talking about it.

Because the thinking "Each blood type have some comonality about their character." is popular in Japan, so if we introducing ourselves  saying "My blood type is..." is not rare in Japan.
A few years ago, the/an ("an"　使うほうがいいです) interesting book "User's manual of own blood type(A or B or ...)" was published and sold over five million copies. (<=ワウ！すごい！)
Inside of the book, there are checklists about ones own blood type's characteristic or possible stories.

However, I think this ("these~are~" はpluralです。) culture are is nonsense...

英語上手ですね。少しだけ直しました。

日本のBlood typeの文化を聞いて面白かったです！がんばってくださいね。

m(^V^)m

Uniqueness in Japan

Teenagers are especially interested in blood types.
They also know what blood types their friends are and sometimes enjoy talking about it.

Because the thought, "members of the same blood type have similar characters," is popular, it is not rare in Japane to introduce oneself with, "My blood type is...". 

Few years ago, the interesting book "User's manual of own bloodtype(A or B or ...)"published and sold over five million copies.
Inside the book, there are check lists about each blood type's characteristics or stories.

However, I think this part of our culture is nonsense...