"Isabella's Lullaby" is a hauntingly beautiful and emotionally charged piece from The Promised Neverland original soundtrack, composed by Takahiro Obata. The lullaby is one of the most iconic and memorable tracks from the series and is associated with the character Isabella, who is both a mother figure and a complex antagonist in the story.

Here is a poignant and emotionally rich piece that perfectly encapsulates the themes of The Promised Neverland. Its gentle yet melancholic melody resonates deeply with the audience, reflecting both the love and the tragedy that defines Isabella's character.