Lines such as "I'll never forget the tears shed in your eyes" and "Devoting itself completely to you" mirror the deep bond between Michio and Roxanne.

The lyrics of "Oath" serve as a thematic bridge between the protagonist, Michio Kaga, and his companions. Key lyrical motifs include:

The "oath" mentioned in the title refers to a commitment to fight and survive within the dangerous Labyrinth, moving forward despite past shadows. Context within the Series

The song reflects Michio's transition from a world he found "hard to live in" to a fantasy reality where he has a second chance.