But, now I am wondering about the word "Great Ring".
Some Japanese pages say it is an American slang.
https://ja.wikipedia.org/wiki/%E7%A6%8F ... B%E7%A7%B0
And a Japanese English page says that "great ring" is American slang referring to the lower part of the female body.
I'm not sure about this story.
If you know about this, please let me know.
Thank you in advance,