So, basically lore-wise it's pretty simple, They are called Songkind, and they have defects based off the song they are "Bound" to. I don't know what kind of music you like, but for example a person bound to "Lemon boy" Would have lemon-themed defects, possibly a leaf or some other thing, or something pertaining to a meaning you see in the lyrics.
When they sing the song they are "bound" to, their voice changes to match the original Audio of the song, so tht means if their song is in a different language they would sing in that language. Same as gender, if say a female is "bound" to a song by a Male vocalist, they will have a more masculine voice.
If another Songkind sings a song that the other one is "bound" to, it can calm the other one down, and even has minor healing properties, such as stopping coughs and congestion, or healing burns or scrapes. Some can use more advanced healing magic, depending on the song.
Rn they are all being held in a goverment facility
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