In November 1999, it was simultaneously released with another album Moon: Wings which has a similar concept. Both albums contain the songs written for the series of Yakai, which had been her conventional plays performed over each December from 1989 through 1998.

Nakajima had a duet with Fumikazu Miyashita on the third track "Into a Dream Someday", a song arranged by David Campbell who also worked on most of Nakajima's albums recorded in the 1990s. Likewise, on the sixth track "I Don't Know Your Language", Campbell's spouse Raven Kane was featured on vocals.

To promote the album, a music video of the lead-off track was filmed. However, along with its follow-up, Sun became one of Nakajima's least successful albums in terms of sales. After those albums were released, she left the Pony Canyon which she had belonged to since debut.

All songs written and composed by Miyuki Nakajima, arranged by Ichizo Seo (except "Into a Dream Someday" arranged by David Campbell).

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Wikipedia