ok i haven't seen the whole video yet so idk if you figured this out, but to answer your question in the beginning, i think the title meaning "voice change" has to do with how the song is about coming of age and growing up. since, for the boys (and for AMAB ppl in general) voice changing is a sign of going through puberty & therefore a sign that they are not kids anymore thats just my interpretation though, i don't speak japanese so i'm not sure if there's another connotation to the word :)
@@belorevideos no problem!! i kind of fell out of properly keeping up with the lore for a while but i've been getting back into it and your videos have rlly helped me catch up :))