The first digital EP by Takaaki Natsushiro."Bluer than indigo"'s the guest vocalist is Suisei Hoshimachi , a virtual singer who belongs to the female VTuber group"Hololive".,Provided to the Project Sekai colorful stage! feat. Hatsune Miku's unit Leo / need"From Tokyo", the new song Soda Light, and the first sound source of"Jellyfish" released on YouTube in April this year. It is a 4 songs work that symbolizes Takaaki Natsushiro in 2021.