song: 【◇合唱◆】六兆年と一夜物語【男女12人】 ( ◇ ◆ [chorus] and six trillion years overnight story [man and woman 12 people] )
I'm not sure what the name's of the vocaloids that sing this are, sorry.
mp3: http://nicosound.anyap.info/sound/sm17818194
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