The fact that the PoPiPa version of Returns is a full minor third/one and a half steps higher than Tae's is really funny to me bc somewhere along the way they must've had a conversation like
"Hmm can we bump this up into C major"
". . . Ok Kasumi we know your voice is super high but why would you voluntarily make yourself hit F5s for no reason"
"Because uhh . . . C major is the easiest key!"
"??? Most of our songs are in other keys and you're fine with those??"
". . . Well! Um! It's symbolism! A 'return' to the uhh . . . simplicity of our roots amirite hehe~"
At which point everyone just gives up and goes with it but hey, it sure ended up sounding nice