"Naisho no Hanashi" (ナイショの話) is a pop song by the Japanese duo and idol unit ClariS, written by Ryo.

[2] Beginning in the A major key, the introduction starts with ClariS' vocals and adds drums and guitars to transition into the first verse followed by the chorus.

Clara and Alice were already big fans of Ryo's music before singing the song and were very excited at the prospect of working with him.

[4] The cover artwork features a translucent ice pop with a bite taken out of it containing frozen fruit with "ClariS" printed on it.

It begins with the illustrations of Clara and Alice by Akio Watanabe, which are shown throughout the video over various rapidly changing patterns.

Animated silhouettes of the girls shown to be running are also seen throughout the video, either alongside the previous illustrations, now semi-animated, or simply overlaid on top of the patterns, some of which are kaleidoscopic in nature.