No one knows exactly what triggered it. Some say it was a quantum audio experiment gone wrong. Others blame a mass psychosis triggered by the show's finale, in which Yuki finally found her brother—only to realize he had been a ghost made of music all along, and that by finding him, she had to let him fade.
gives the score a 4/5, noting its emotional engagement. Notable tracks from the listings include:
Midnight approached. The bubbles began to slow. They had been drifting chaotically for fifteen years, but now they started to organize themselves into ranks, like a choir taking their places. Rin watched the diagram on her phone. The path was almost aligned. anime bubble soundtrack
The soundtrack features two main theme songs performed by popular Japanese artists:
: The energetic opening theme that sets the stage for the film's post-apocalyptic Tokyo. "Battlekour" & "Parkour" No one knows exactly what triggered it
—famed for his work on Attack on Titan and Promare —the score is designed to match the breathtaking kinetic energy of WIT Studio's animation.
She adjusted her earpiece and synced it to a small transmitter she had rigged to the piano's soundboard. The transmitter would capture every note Kaito played and broadcast it into the bubble field, filling the missing gaps in the soundtrack. gives the score a 4/5, noting its emotional engagement
Kaito stared at the diagram. His musician's brain, dormant but not dead, began to trace the path. He saw the rhythm in the spacing of the bubbles. He saw the harmony in the way the lines intersected. He saw the shape of a song—a requiem, a farewell, a promise.