Title: 誰がその鍵を壊すのか
Romaji: Dare ga Sono Kagi wo Kowasu no ka
Translation: Who’s going to break that lock?
Arrangement: Linjin [ZYTOKINE]
Lyrics: Linjin [ZYTOKINE]
Vocals: Ranko

Original theme:

• Locked Girl ~ Shoujo Misshitsu – Bouyu Toukaidou ~ Retrospective 53 minutes; track 9

Album:

• Shiro ni mo Kuro ni mo Narenai Kimi e [ZYTOKINE] (disc 1, track 3)