Hi Prikarin!
It's absolutely okay! I apologize for the delay. There were multiple composers whose music was used. I'll list them below. Some of them have limited social media to follow, or none at all.
Jianteng - https://dova-s.jp/_contents/author/profile179.html
MFP【Marron Fields Production】 - https://x.com/Kurippermusiq
Make a Field Music - https://www.make-a-field-music.com/about
のる - https://x.com/noru_with_piano
Brightwaltz - https://x.com/brightwaltz
風人 - https://x.com/Kazinchu_dtm
かずち - https://x.com/kazuchikatch
いまたく - https://x.com/imatakunoshin
ハモおた - https://x.com/hmotclassical
佐土原隼人 - https://hayato-sadohara.com/euh56776/
GANO - https://gano.chords-map.net/lp/music/
Fukagawa - https://x.com/FukagawaShota
Ilodolly - https://merrybad.com/
作曲Kimy - (No Social presence. They've stopped distributing music at present.)