Net Terminal Genes

The universe of the manga Blame! created by Tsutomu Nihei is home to the following fictional characters and locations:

The Safeguard are a program independent of the netsphere. The netsphere was designed as a means of providing service to those who could log on. However, the netsphere was thrown into chaos (the actual reason is not exactly known, but the prequel manga NOiSE implies that a small group of humans is at fault) and the Safeguard changed their modus operandi from preventing unauthorized users from entering the netsphere to killing off anyone who does not possess Net Terminal Genes. The Safeguard have nine levels of hierarchy, Level 9 being the most powerful. However, their Exterminator (originally the lowest level safeguard) system has a different form of hierarchy where "First Class" is the most powerful.

Safeguard Exterminators seem to run on a different protocol of command than the higher level of Safeguard such as Sanakan and/or Dhomochevsky (though Dhomo did have a contingent of them assigned to him before Schiff destroyed them). At one point, the Exterminator Class One even targets Sanakan as it deems her a threat or obstacle, but does not decide to kill her. It is up to speculation as to why - perhaps either it no longer saw her as a threat, or perhaps it was because she too was a Safeguard.

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