I think I'm going to make a guess. Maybe the last song is overlapping with perspectives of Maribel (while in Gensokyo) and Renko (in the outside world), like how in the album cover they overlap with different perspectives.
It's the Schrodinger Wave Function in the first few seconds. The album cover is a gif that fades to both side periodically, the song list as A/B is combined in one row. The entire album concept seem to be circle around that idea
