12th Digital Single "Prussian Blue" Credits Music & Lyrics by Hitomi Kuramoto Vocal : hitomk Piano : Yoko Hiromoto Bass : Yan-G Drum : Shoji Hiraya Flute : Hajime Yamamoto Arrangement : Yoko Hiromoto Description Executive Producer : Hitomk Sound Producer :Akira Horie Recorded & Mixed by : Katuyuki"Koba-yan"Kobayashi Recording Engineer : Takeshi Kawano Mastered by : Yasuji Maeda at Bernie Grundman Mastering Tokyo Recorded at : Geimori Sutudio , Kawano Onkyo & SOUND CREW STUDIO Artwork Design : Akemi Nagahari