Unfortunately, this song was not included in the official OST.
If this song had been included in the OST, it would have been called 契約意識 (Contract consciousness).
Since the sequel smartphone game Engage Kill failed and shut down, there was no chance of this song being released, so I used AI to create this song.
For the first half, I removed the voices using the ULTIMATE VOCAL REMOVER V5 from some scenes from episode 11, and then used RipX DAW to remove noise.
The second half was added using the BGM from the BD Menu 04-06 footage.
ANIME