Kyoto Inks Kyo No Oto No.07 Fountain Pen Ink - HisokuAbout Kyoto Inks Kyo No Oto No. 07 Fountain Pen Ink Hisoku Hisoku is in Kyoto Inks Kyo No Oto range of exclusive Japanese inks and is presented in a 40ml glass bottle, elegantly packaged in a thick card box. Hisoku is a pale blue green ink , translated it means secret colour. The secret colour is a pale blue green colour like the colour of blue porcelain, and the colour name comes from the mysterious beauty of the ash tinted blue green colour peculiar