誕たん生じょう秘ひ話わ

noun

untold story behind the creation; secret origin story

Refers to the hidden or little-known background of how something came to be, often used for products, works of art, or events. Carries a slightly dramatic or promotional tone.

• この映えい画がの誕たん生じょう秘ひ話わを聞きいて、ますます好すきになった。

  Hearing the untold story behind this movie made me like it even more.

• 新しん商しょう品ひんの誕たん生じょう秘ひ話わが公こう式しきサイトで公こう開かいされた。

  The secret origin story of the new product was revealed on the official website.