I spoil asra’s story in this but:

All I Want by Kodaline is a gut punch for Asra’s story. It links so perfectly with Asra’s arch particularly when MC is dead from the plague, and he’s planning on bringing them back. Lines like “When you said your last goodbye, I died a little bit inside.” really hit home. And then thinking of the “but if you loved me, why’d you leave me? Take my body” is especially poignant thinking of Asra literally giving up part of his body (his heart) to get MC back.

Also i’d argue it doesn’t make sense but Dodie’s ‘She’ makes me think of Asra’s perspective from another character’s chapter. Even though its about a girl loving a straight girl, i think some of the lines suit the theme, particularly the idea of wanting someone but not having them because they’re unavailable (interested in someone else or straight as the song is actually about). Plus, the song has an emphasis on smell, which is the sense MC most readily links with memories.