History for Wearingeul Yi Sang Thirteen Children

Wearingeul Yi Sang Thirteen (13) Children comes in a square 30 ml glass bottle. The ink starts as a dark blue colour, but dries into a blueish green, or deep teal. Wearingeul says that this "illustrates the fright of the 13 children". The ink has a red sheen, and some shading.