I also saw the full tracklist today, and unfortunately you have to buy at least 3 of the versions to get all the songs, but this is fairly common
I think I'll only buy 1 or 2, but 3 or 4 is a bit excessiveto me, even for Ruri <3 I'll usually find which b-sides I like the most and get those versions (this causes problems in the past, like Maeda Atsuko singles...all 4 of the b-sides were amazing
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