>>4092396I made a playlist dedicated to her some time back of songs I either associate with her or that fit her story arc (sans Rebellion because that Homura is too dear for description).
Besides Mebius Ash, Inevitabilis, the OPs and EDs, and Yumeoto -- because those are obvious -- I would associate Penguin Cafe Orchestra's "The sound of someone you love who's going away and it doesn't matter" with her the most.
The song is a journey through gazing at someone, getting closer to them, simmering together like leaves in the sun, all while the illusion of perfect happiness collapses, culminating in the broken and teary sounding violin stings. There's nothing that describes Homura's arc so well.