I listened to the song. The interplay between Teto and GUMI was absolutely beautiful and wonderful. I really love this track! The piano in the intro is a particular favorite of mine. By the way, how did you achieve Teto's shout? I was so surprised when I heard it—I had no idea she could produce a voice like that.
Thank you! Yeah, the idea of this interplay popped into my head very spontaneously, but it felt so natural that it essentially became the backbone of the whole narrative. I'm glad you liked it!
As for Teto's shout, we basically followed this guide.
I just fiddled with her settings (added more "power" and "rock," increased breathiness, lowered the gender parameter, and decreased voicing a bit), applied the script mentioned in the video after finding the settings that I liked, and then we added some distortion during mixing, also adding some real growls as back vocals to support her voice.