The manhwa is licensed in North America by Infinity Studios,[1][2] in France by Tokebi[3] and in Russia by Comics Factory.

[5] Its sequel, Zero: Circle of Flow (Hangul:제로 - 흐름의 원, RR: Jero - Heureumui won) is a Korean manhwa written by Dall-Young Lim.

[7][8] From Infinity Studios: Having been born in a secret government laboratory that cultivated esper (Extrasensory Perception) powers with humans, Shuuichi and his two sisters, Sumire and Katsumi, are forced to endure a difficult life as test subjects until their escape.

Years later, these siblings are still being sought after by unknown organizations that are after Shuuichi's powers as he is what they refer to as a "Zero Sample" with the ability to cause "Zero Shock".

Born in 1961, An artificial life form created from the genes of Shuiichi's dead mother with the purpose of being a generator of SG capable espers.

Being the daughter of Shuuichi this would make her a 3rd gen "zero sample" however her power is never seen other than the fact that she can pilot the "SG Armor" Born in 1958, she is currently the Senior Research Agent of Tokyo's ESC Division.

Only appearing in the epilogue chapter, Kei has the same abilities as Shuuchi and is a third generation Zero Sample In the bonus section of the end of the first volume, Dall-Young Lim talks about his difficulties in trying to adapt the manhwa, target at older teens, from its adult game.