Hisashi Igou

Age - 17 / Height - Original: 178cm (Anime version: 176cm) / Weight - 64kg

A key person in the story. He has a calm personality and possesses accurate situational judgment. He is a black belt in karate. According to Takashi, he is "skilled in both academics and sports."

Takashi's former best friend. From Takashi's flashback in Volume 4, they have known each other since at least middle school. Despite knowing Takashi's feelings, he dated Rei, ultimately betraying him, which led to their estrangement.

In Episode 1, after being bitten by Wakisaka, who had turned into "one of them," he vomits blood and becomes the first proven case of "being doomed just by being bitten." He agonizes, lamenting that he doesn't want to become "one of them," and just as Takashi, understanding his former friend's feelings, is about to finish him off, Rei stops him. He then turns into "one of them" and is put down by Takashi.

Regarding the living dead, he created the term "them" because "it's not a movie or game, so we can't call them 'zombies'." According to Saya's later interpretation, this was because he realized the possibility that they would have to continue fighting "those who should be human."

Due to the aforementioned incident, he remains a complex presence that continues to trouble Takashi. The original author, Daisuke Satou, also despised him, calling him "someone who deserved to die," and it was revealed that he was planned to die from the initial draft.

His name is an anagram of the manga artist Go Nagai, and his personality and actions are influenced by Nagai's works.

Anime version

In the original, he is depicted as having a strong possessive side, such as grabbing Takashi, while in the anime version, there are depictions suggesting he feels guilty towards Takashi, emphasizing his conscientious side.