Summary:
- Gaku makes his terrifying debut, turning Sakamoto Days into an unpredictable slaughter-fest of chaos.
- Raised in a death camp, saved by a killer, Gaku fights like life’s just a game.
- One punch, one kill, Gaku redefines fear in Sakamoto Days with zero remorse and maximum carnage.
Sakamoto Days Episode 15 (Part 2 Episode 4) introduced one of the strongest characters of the anime. His name is Gaku, the walking apocalypse in a hoodie. Let’s be honest, you probably had to pause the episode for a breather the moment that he casually obliterated a JAA agent with a single punch. So, who is this menace, and why is he the most terrifying wildcard of the entire anime? Here’s everything you need to know about Gaku in Sakamoto Days.
Table of Contents
Gaku’s Origin: Raised for Violence, Born for Chaos

You don’t become Gaku without having a brutally twisted past. Raised at the Al-Kamar Orphanage, a secret JAA assassination training camp, Gaku grew up surrounded by bloodshed, betrayal, and nonstop psychological trauma.
He was not alone, however; other orphans like Uzuki and Kumanomi were also subjected to this vile experiment. And yes, it was every bit as disturbing as it sounds.
Gaku was already being used and manipulated by the age of 13. His so-called “guardian,” Sei Asaki, used emotional abuse and manipulation to pressure Uzuki into taking missions. All of this changed when Uzuki finally snapped.
He broke into Al-Kamar, slaughtered the guards, and freed Gaku and the others. What did Gaku do with his freedom? He joined Uzuki’s organization, Slur’s group, without hesitation.
Gaku’s Introduction in Sakamoto Days

Sakadays Episode 15 (Part 2 Episode 4) marks Gaku’s big anime debut, and oh boy, what an entrance. He walks into the JAA Tokyo Bureau with Slur, and before you can even react, he punches a JAA agent so hard that his torso disintegrates. That wasn’t just violent, it was a statement.
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Then Gaku follows orders from Slur and basically tears the building apart like a whirlwind of chaos. Staff? Gone. Guards? Annihilated. And when he encounters Takebe’s unit and even Inoda, and you think, maybe this is where he slows down? Nope. He tanks a punch from Inoda, shoots him in the face with a hidden gun inside his mace, then bludgeons him through buildings like it’s nothing.
Gaku vs Takamura: The Fight That Nearly Killed Him

Even Gaku has his limitations, and his limitation is named Takamura. This fight? Brutal. You get to witness Gaku experience fear, and rightfully so. Takamura slices off parts of Gaku with the ease of peeling an orange. We’re talking an ear, two fingers, and a complete arm amputated in a matter of seconds.
But what’s even scarier is how Gaku deals with it. He doesn’t scream or freak out. He kicks his cut-off arm at Takamura as a diversion and attempts to continue fighting. That sort of psychotic toughness tells you everything about this man.
Gaku’s Powers: Monstrous Strength, Gamer Mentality

Let’s talk about Gaku’s powers and abilities:
- Superhuman Strength: He pulverizes individuals like bugs, often with one backhand.
- Superhuman Speed: Capable of dodging bullets and landing hits before anyone can react.
- Durability & Endurance: He battles through blown-off limbs as if nothing’s happened.
- Combat Skills: A master with his mace and terrifyingly skilled at close combat.
What sets Gaku apart isn’t his power, though. It’s his twisted, unpredictable mindset. Gaku fights like he is in a video game. He once called a potentially fatal wound a “speedrun to death” at one point. And sure enough, he casually eats snacks and plays games mid-fight. You can’t predict a guy like that. He’ll be joking around one second and crush your skull the next.
Gaku’s Relationships: The Only People He Cares For

Gaku might seem like someone who doesn’t care about anything, but he is extremely loyal to Uzuki and Kumanomi. Here’s why:
- Uzuki (Slur): The man who saved him from the orphanage. Gaku considers him a leader he’d die for.
- Kumanomi: Pretty much the only family Gaku has. She takes care of him like a big sister and even cries when he gets hurt.
Gaku further shares a mutual hatred for Takamura, although “hatred” is perhaps even too weak a word. We can only say that if Gaku does somehow get a second chance with him, it’s going to be ugly, and he’s 100% going to enjoy it.
Gaku’s Role After Episode 4: The Quiet Bomb Waiting to Explode

After that explosive introduction, you don’t see Gaku jumping into every battle. Instead, he hangs out at Slur’s hideout, reattaching limbs as if it’s arts and crafts, and plotting the next course of action with Kashima. Don’t mistake his inactivity for irrelevance, though. Whenever he’s in the room, the air is charged with tension. Because when he does act? People die.
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In the JCC Transfer Exams, he controls Shinaya remotely, bringing the guy down to the level of a human puppet just to scout out potential recruits. And of course, he does it while playing a video game. You know, whatever comes next with Gaku will change the direction of the entire series.
Gaku’s Role in Sakamoto Days
You’ve seen assassins before, sure. But Gaku is different. He’s what you get when unstoppable force meets zero empathy and is handed a game controller. He’s terrifying, unhinged, and utterly entertaining to watch.
Whether he’s clearing out JAA agents or playing a life-or-death battle like a side quest, there’s one thing for sure: Gaku’s not leaving anytime soon. So if you’re caught up through Sakamoto Days Part 2 Episode 4, you already know: Gaku is chaos personified. And somehow, you love watching every second of it.