Re:ZERO Season 4: Why Did Subaru Lose His Memory? Arc 6 Twist Explained
Re:ZERO -Starting Life in Another World- has always been willing to put Subaru Natsuki through psychological hell, but the Arc 6 storyline takes that idea to an entirely different level. The moment Subaru wakes up inside the Pleiades Watchtower with no memory of his life in the isekai world is easily one of the most disturbing twists in the entire story.
Imagine spending years of your life fighting monsters, surviving impossible deaths, building friendships, and becoming someone people genuinely depend on—only to wake up one day and realize that none of it exists in your head anymore. Emilia is a stranger. Beatrice is a stranger. Ram, Anastasia, and everyone else who trusts Subaru suddenly means absolutely nothing to him.
And the cruelest part? Subaru doesn’t even understand why everyone expects so much from him.
For me, this is what makes the infamous “Amnesiabaru” storyline so fascinating. It isn’t simply another anime character losing his memories so the plot can create temporary drama. It forces Subaru to confront a question that has been hiding underneath the entire series: Is Subaru the person he remembers being, or is he the person he became through all the suffering?
Why Was Subaru in the Pleiades Watchtower?
The events of Arc 6 take place in the mysterious Pleiades Watchtower, a legendary structure hidden within the dangerous Augria Sand Dunes. Subaru and his companions arrive there with a very specific goal: find the Sage and uncover a way to solve the devastating problems caused by the Witch Cult’s Sin Archbishops.
The situation is already desperate. Rem is still trapped in a coma after losing her name and memories, while Julius has effectively been erased from the memories of most people around him. The group desperately needs answers, and the tower seems to be their best chance.
Unfortunately, the Pleiades Watchtower is not exactly a friendly place.
One of its biggest mysteries is the Taygeta Library, a massive archive containing the legendary Books of the Dead. These aren’t ordinary books. Each one contains the memories and experiences of a deceased person, allowing someone who reads one to experience that person’s entire life.
That concept alone is already unsettling. But Subaru eventually discovers that these books can interact with something far more dangerous than simple memories.
The Empty Book That Changed Everything
Subaru’s biggest problem inside the tower is Reid Astrea, the legendary First Sword Saint. Reid is essentially a walking nightmare for anyone trying to pass the tower’s trials. His strength is so absurd that even experienced fighters struggle to survive against him.
So Subaru does what Subaru does best: he comes up with an incredibly risky plan.
He decides to search for Reid’s Book of the Dead. The idea is simple enough. If Subaru can experience Reid’s memories, perhaps he can discover some kind of weakness or insight that could help them overcome the trial.
But there is one enormous problem.
Reid’s book is empty.
This isn’t because Reid never lived a life worth recording. The situation is much stranger. Reid’s existence is directly connected to the tower and its trials, meaning his memories are being used in a way that makes his Book of the Dead fundamentally different from the others.
When Subaru opens the book, he doesn’t receive a normal memory playback. Instead, the empty pages become something much more terrifying—a doorway into the mysterious Corridor of Memories.
And that’s where everything goes completely off the rails.
Louis Arneb Was the Real Nightmare
Inside the Corridor of Memories, Subaru encounters Louis Arneb, one of the most terrifying members of the Witch Cult and a Sin Archbishop of Gluttony.
Louis is unlike the other members of the Gluttony trio. While Lye and Roy operate in the physical world, Louis has a much stranger connection to the realm of memories and souls. She exists in an environment where memories can be consumed, manipulated, and stolen.
When Subaru suddenly appears in front of her, Louis immediately recognizes that something about him is different.
And this is where I think Arc 6 becomes genuinely brilliant.
Subaru isn’t just another victim for Louis to devour. His existence is completely abnormal. His experiences, his deaths, and the mysterious power he carries make him an incredibly valuable target.
Instead of simply consuming everything Subaru has experienced, Louis takes a more complicated approach. Through the Authority of Gluttony, she creates a fragmented version of herself and attaches that consciousness to Subaru’s soul.
The result is catastrophic.
Subaru’s memories of the isekai world become inaccessible. They aren’t simply deleted like files from a computer. Instead, they are effectively sealed away, leaving Subaru with the memories of his original life in Japan but almost nothing from his journey after being summoned.
| What Subaru Remembers | What Subaru Forgets |
|---|---|
| His life in Japan | Being summoned to the isekai world |
| His original personality and past | Emilia and his relationship with her |
| His memories before the convenience store incident | Beatrice and his bond with her |
| His identity as Natsuki Subaru | His battles, deaths, friendships, and achievements |
Welcome to the “Amnesiabaru” Arc
Subaru waking up without his memories is one of those moments that completely changes how you look at the character.
Everyone around him sees a hero.
Subaru sees a complete stranger.
Emilia trusts him. Beatrice cares deeply about him. His companions rely on him because of everything he has accomplished. From their perspective, Subaru is the person who repeatedly stepped forward when everyone else was ready to give up.
But the Subaru who wakes up in the tower doesn’t know any of that.
As far as he’s concerned, he’s still the insecure Japanese teenager who was suddenly transported to another world. He doesn’t understand why these people love him. He doesn’t understand why they believe in him. Most importantly, he doesn’t understand how he could possibly become the person they describe.
And honestly, this is where the story becomes incredibly uncomfortable—in the best possible way.
Subaru is forced to live alongside the reputation of a version of himself he doesn’t remember becoming. Every compliment feels suspicious. Every expectation feels impossible. The people closest to him are essentially telling him, “You’re amazing,” while his own mind is screaming, “I’m not that person.”
It’s a fascinating reversal of the usual Re:ZERO formula. Normally, Subaru remembers every horrible thing that happened while everyone else forgets. This time, everyone remembers Subaru—but Subaru doesn’t remember himself.
Louis Makes the Situation Even Worse
Unfortunately, Subaru isn’t alone inside his own mind.
The fragment of Louis connected to him continues to influence the situation. Her presence becomes another layer of psychological horror as Subaru struggles to determine what is real, what is manipulation, and what is actually his own decision.
Some of the darkest moments involve Subaru’s body being used against his will. The story pushes him into situations where he can no longer trust even his own actions, creating a disturbing sense of helplessness.
For a character whose greatest strength has always been his determination to keep moving forward, taking away his memories is almost the perfect punishment.
How can Subaru save everyone when he doesn’t even know who he is anymore?
Does Subaru Lose His Memories in Re:ZERO Season 4 Part 2? The Loss Arc Explained
How Does Subaru Get His Memories Back?
The answer is one of the most emotionally satisfying parts of Arc 6.
As the situation inside the tower becomes increasingly chaotic, Subaru eventually discovers his own Books of the Dead. Because he has died multiple times, his existence has left behind records within the Taygeta Library.
Subaru then does something that is both incredibly dangerous and completely fitting for his character: he reads his own story.
By confronting these records, Subaru is forced to face the person he used to be—the version of himself who experienced every death, every failure, every desperate victory, and every moment where he chose to stand back up.
What follows is not simply a battle between Subaru and Louis. It’s a confrontation between two versions of Subaru himself.
On one side is the amnesiac Subaru, who sees himself as weak and unworthy.
On the other is the Subaru who remembers everything.
Every death.
Every scream.
Every person he failed to save.
Every friend who believed in him.
Instead of one version completely replacing the other, Subaru ultimately comes to understand that both are part of who he is.
The Real Meaning Behind Subaru’s Memory Loss
In my opinion, the biggest twist of the entire Arc 6 memory-loss storyline isn’t actually that Subaru forgets everything. The real twist is what he learns by temporarily becoming a stranger to himself.
Subaru finally realizes that the “hero” everyone talks about was never some naturally fearless protagonist hiding underneath his insecurities.
There was no secret perfect version of Subaru.
There was only a scared, flawed, stubborn teenager who kept choosing to move forward.
That’s the point.
Subaru’s accomplishments aren’t impressive because he’s secretly the strongest person in the room. They’re impressive because he was terrified, exhausted, and broken—and he still refused to stop trying.
When Subaru regains his memories, he isn’t simply restoring lost information. He’s reclaiming the entire weight of his identity.
And that’s why the Arc 6 twist works so well for me. The story temporarily removes everything that made Subaru “Subaru,” only to force him to discover that his greatest strength was never his memories in the first place.
It was his choice to keep going.
Final Thoughts
The Re:ZERO Arc 6 memory loss twist is easily one of the most ambitious psychological storylines in the series. The combination of the Pleiades Watchtower, the Books of the Dead, Louis Arneb, and the Corridor of Memories creates something much more complicated than a standard amnesia plot.
What makes “Amnesiabaru” so memorable is the uncomfortable question sitting underneath everything: Would Subaru still choose to be the same person if he had no memory of all the suffering that created him?
Arc 6’s answer is ultimately yes—but not because Subaru magically remembers that he’s supposed to be a hero. He has to confront his own past, accept the person he became, and understand why the people around him chose to believe in him.
For longtime Re:ZERO fans, this is exactly the kind of brutal character writing the series does best. Subaru loses his memories, loses his confidence, loses his understanding of the people closest to him, and even loses trust in himself.
And somehow, after all of that, he finds his way back.
That’s what makes the Arc 6 twist so powerful—and why the “Amnesiabaru” storyline remains one of the most talked-about moments in Re:ZERO.
