It’s confusing but explainable.
Summary:
- The Chainsaw Devil has the ability to consume devils.
- This erases them from existence, history and people’s memories.
- There are still some things about the Chainsaw Devil’s ability that are unclear.
Chainsaw Man devils exist for as long as their name is known and feared, as they feed on humanity’s fears. Apart from various other abilities, Pochita has one to erase devils from existence by consuming them.
Devil erasure
When a devil is eaten by Pochita, their name and physical existence vanishes from public consciousness, so no one can remember about certain events anymore. Chainsaw Man characters have no recollection of some historical events such as World War II, which means that the Chainsaw Devil consumed its respective devil at some point in the past.
This led fans to wonder how exactly this process works. We know that the war did indeed happen, and the Chainsaw Devil consumed the WW2 Devil afterwards. Would that mean that people just forgot 6 years of their lives, during which the war was going on? And how can all the destruction be explained then?
But the Chainsaw Devil’s power doesn’t work like that. When a devil is consumed and their name is erased from existence, it’s not only a matter of recollection, it’s the event itself.
So when Pochita consumed the WW2 Devil, it changed the past in a way, so the people don’t just forget about the war; the war never happened for them, so there’s no destruction or blank 6 years of their lives.
The same with other devils that have been consumed by the Chainsaw Devil. Characters in the series don’t know what Holocaust or nuclear weapons are, so that means their Devils don’t exist anymore, either.
This means that the atomic bombings of Hiroshima and Nagasaki never happened and the cities were never destroyed.
Things we don’t know yet
There are still some things about Pochita’s powers that are unclear, but the main idea is that it rewrites history in a way. The fact that the Soviet Union still exists in 1997, when the story of Chainsaw Man takes place, is a good enough reason to believe that, since the USSR was declared dissolved in 1991.
The fact that Makima was able to remember some of the erased names also gives us a hint that there’s still much we don’t know about Pochita’s ability. Still, Makima was always special. She’s one of the Four Horsemen after all, so she might just be an exception.
And we can’t also forget that the War Devil wanted to force Pochita to give the Nuclear Weapons Devil back, so that means there’s still a way to rewrite history again and bring the erased devils back.