Mayuri’s character arc explores the tragedy of a "life born to disappear." Her final confession—that she was born to love Shido rather than just serve a functional purpose—serves as the emotional core of the film.
As Shido successfully completes his dates, Mayuri's role ends, meaning she must disappear. However, she develops her own feelings for Shido, causing her Angel, Kerubiel , to react to her latent jealousy and go berserk.
Mayuri's Angel, Kerubiel, is named after the Cherubim , the angels who guard the Garden of Eden. Her final weapon, Lahatherev , refers to the "flaming sword" mentioned in Genesis.
Ratatoskr determines the sphere is a manifestation of the collective stress and "Reiryoku" (Spirit power) from the spirits Shido has already sealed. To stabilize this energy, Shido must go on individual dates with all the Spirits to improve their mental state.
Critics and fans highlight several thematic layers within the film: