Meet Satoru Fujinuma: time-traveler extraordinaire. Well, maybe not “extraordinaire.” He’s pretty ordinary. And he can’t even control his time travel ability. Titled “revival,” his ability randomly throws him back in time to a point where he has the opportunity to save a life. Normally this takes place as little trips 5 minutes back in time, but the primary arc of Erased follows Satoru going back 18 years, back into the body of his elementary school self. He now has to find a way to prevent a series of child murders, including that of his former classmate, Kayo Hinazuki.
I attribute to Satoru the generic tragic flaw of pride. Pride is what leads to his failures, i.e., being unable to save Kayo. It is Satoru’s pride that blinds him with confidence when Kayo’s death is delayed a day; he thinks that he has the ultimate power to resolve the tragic event by himself. But, like in other time travel tragedies, Satoru is able to overcome that pride and accept in the assistance of his friends and his mother in order to solve the mystery behind the serial killer and “erase” the tragic event from history.
Much like the next entry, Orange, Erased acts primarily as a mystery. The fight against fate is futile, and even with Satoru babysitting/ giving sanctuary to Kayo, she still inevitably dies. So the mystery must be solved, the rules of this universe discovered, and a plan executed to prevent the tragic event.
The Butterfly Effect is not overtly present in Erased. But it does show up with the conclusion: due to the changes that Satoru made in the past and the friendships made and grown, we see a vastly different future for Satoru.
And then we have our god: Gaku Yashiro-Sensei. Also our villain. He is the serial murderer, as well as the law of nature that punishes Satoru’s pride. It is Satoru’s pride while being ignorant or helpless that Yashiro-Sensei exploits in order to murder all of the young girls. But when Satoru overcomes his tragic flaw, Yashiro-Sensei is overthrown and exiled. Though not without cost. Satoru’s self-sacrifice is his alternate tragic event, and he is put into a coma for fifteen years. But he is victorious otherwise. Everyone is still alive, and he wakes up to be able to defame and convict Yashiro-Sensei. The end. Happily ever after.