what is the song one last time about
"Earth will pass catastrophically through the tail of the comet Eurydice in one week. Gather family and lovers close, one...last...time".
One Last Time (Ariana Grande song)
 "Earth will pass catastrophically through the tail of the comet Eurydice in one week. Gather family and lovers close, one...last...time". 
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One Last Time (Ariana Grande song) [SEP] Background
Gillies previously appeared Grande's music video for her single "Right There" (2013). Around that time, Max Landis revealed "One Last Time" as Grande's next single after tweeting, "Earth will pass catastrophically through the tail of the comet Eurydice in one week. Gather family and lovers close, one...last...time". The lyric video for "One Last Time" was released on Grande's official Vevo on February 6, 2015, at the same time it was announced that the music video was finished. On February 12, 2015, three days before the release of the music video, Grande released a teaser of the music video via Instagram.