The Girl Who Closed Her Heart

 is Disc 1, Track 22 on the Xenosaga Original Soundtrack and Disc 1, Track 5 on the album. ('The Girl Who Closed Her Heart' is an unofficial translation, as seen in the VGMdb listing of the album.) is a remix of this track. The melody at the start is similar to that of and its derivatives.

It plays in the following cutscenes:
 * Cherenkov tells Shion his tale on the Beach of Nothingness after the fight.
 * Nephilim tells Shion that she must accept all of her memories.
 * KOS-MOS and chaos talk briefly before she steps out to protect the Elsa as it falls to Second Miltia.