Here's my headcanon playlist/music rotation for Sora and Strelitzia in their Quadratum apartment for my fic! I started with an Utada song because it felt like I had to, otherwise this is in a fairly specific order (to me - you can shuffle it if you want, and Sora/Strelitzia def shuffle it too so it doesn't really matter).

You will notice that it is all Japanese music and ALSO that there are no anime openings/endings (unless I missed something - I tried to double check every song here, but struggled with a few because I can read Hiragana and Katakana but not Kanji so I was very ???? with the songs titles that had lots of/only Kanji), I did this because it makes sense with my internal logic of Quadratum, but that's just my personal vision! I hope you enjoy!!