|I picked the wrong regiment to join. As long as you guys have it in you to risk your lives and keep fighting... I will trust you.|
|— Marlo to Jean about the Scout Regiment|
Marlo Freudenberg (マルロ・フロイデンベルク Maruro Furoidenberuku?) was a recruit (新兵 shinpei?) in the Scout Regiment, and a former private (二等兵 nitōhei?) in the Military Police Regiment stationed in Stohess District. He was a graduate of the 104th Cadet Corps, though he was not from the same division as Eren Jaeger.
Marlo was a tall young man with a diamond-shaped face, black bowl-cut hair, an aquiline nose, and small, intense, gray eyes. He usually wore his Military Police Regiment uniform before joining the Scout Regiment and was rarely seen without a stoic and serious expression on his face.
Marlo was a very righteous person. While most who join the Military Police Regiment do so because they want a safe position far from the danger of the Titans, Marlo did so because he wanted "to uphold justice and do what's right." His goal was to rise to the top of the organization so he could stop the pilfering of taxes and misappropriation of land. Though steadfast in his idealism, he could make moral compromises to achieve his goal, confessing a willingness to act like "scum" in order to move up in rank. Due to his passion towards his ideals, he had often been compared to Eren by people who know both of them.
He initially held a belief that human beings are naturally benevolent and righteous, accompanied by something of a black-and-white view of morality. He was aware of the Military Police's corruption and had the intention of making its members feel shame for their transgressions when he rose to the top, comparing them to animals that defecated wherever they felt like. He soon came to realize, however, that the system itself is the one that encourages the corruption and inherent selfishness of human beings.
He is later convinced that he chose the wrong regiment and unofficially entered the Scout Regiment, later making his branch change official. Prior to leaving, Marlo was seen showing excitement about the upcoming mission to reclaim Wall Maria.
When Annie Leonhart is tasked with searching for the missing girl Carly Stratmann, she consults Marlo for information concerning the Stratmann family and Marleen company, owned by Elliot G. Stratmann. Marlo informs her of the company's profitable business between Wall Maria and Wall Sina and the inevitable decline in business following the fall of Wall Maria, reducing the company to a carriage business. Annie wonders if Marlo is being forced to pursue the investigation like she has been, but Marlo insists he is keeping records for the good of the Military Police, unlike his peers.
A few days after the 57th Exterior Scouting Mission, Marlo is assigned to guard the Scout Regiment convoy transporting Eren Jaeger as it passes through Stohess District. When he questions why they need to accompany the Scout Regiment through town, his superior leaves Marlo in charge of the mission.
Frustrated by the higher ranking officers' lack of morals and duties, Marlo explains his motivation for joining the Military Police to the other recruits. He goes on a tirade about how the Military Police are no better than animals, and when he is in charge he will make them into what humans are supposed to be. This prompts Annie to speak up, commenting that she believes having someone like Marlo in charge would only be a detriment. She compares Marlo to an acquaintance of hers, commenting that they are both idiots trying to go against the flow of the world. Marlo simply retorts that if her friend is an idiot then they are nothing alike, before ordering the squad to begin their assigned patrol.
While on duty, Marlo sees and confronts higher ranking officers that are illegally selling omni-directional mobility gear to the merchant association. When he threatens to report them, they beat him up. Annie and Hitch intervene, and the officers decide to let him off the hook. Enraged, Marlo begins to reach for his rifle, considering executing them while their backs are turned. As he wrestles with his desire to kill them, Annie offers to help him, reminding him of his desire to punish the corrupt. Annie's words cow Marlo, and he allows the officers to leave. Frustrated with himself for not following through, Marlo asks if the friend Annie had compared him to would have killed them. Annie confirms the possibility, and Marlo laments that he is just like the others in their squad, going with the flow of the world.
After the fight between Annie and Eren begins, Stohess is in utter ruin and Hitch can be seen on a rooftop with Marlo and other soldiers, questioning why there would be Titans fighting inside of Wall Sina.
After the aftermath of Eren and Annie's brawl in Stohess, Marlo and Hitch are seen looking at the rubble from the buildings and bodies scattered all over. Marlo wonders why they are being kept in the dark when they had just fought a Titan this far inside the Walls and Hitch replies that it is business as usual and notes that there is not an "official" reason why all these people died.
Marlo and Hitch are assigned to patrol a forest outside of Trost, in search of Scout Regiment fugitives. The two at first exchange satirical responses about being placed with one another, but the talk progresses into a discussion about the Scout Regiment. Hitch blames the Scouts for the destruction in Stohess District, but Marlo points out that the Scouts captured one of the Titans, something no other Military branch could have done.
The conversation is cut short when they encounter Armin Arlelt, who is apparently gathering water into bowls. They order him to raise his hands but are jumped by Levi and Mikasa, who take their guns and strip them of their weapons and uniforms. Marlo and Hitch are interrogated and Marlo is shocked to see Hitch confront them about their actions in Stohess. Upon blaming them for Annie's death, Levi reveals to Hitch and Marlo that Annie was the Female Titan that caused significant damage to the city and that she is alive and in custody. Marlo claims that he wants to help Levi and the others, but Levi refuses and orders that they be taken away and released.
They are led away by Jean Kirschtein, who reveals that he intends to kill them both as they are a threat and can not be trusted. He trips and drops the knife, and Marlo tells Hitch to run while he holds off Jean. As they struggle for the knife, Marlo convinces Jean he is on their side by confessing his discontent with the Military Police, saying that he trusts the Scouts to lead humanity to victory. They both stop struggling, and Hitch ambushes Jean, bashing him in the head with a tree branch. She attempts to hit him again but Marlo stops her and explains that Jean was only testing them.
Following the coup, Marlo transfers to the Scout Regiment, enthused for the upcoming mission to save Wall Maria. When asked about Hitch's reaction to his transfer, Marlo says that Hitch berated him and tried to convince him to instead live the easy life in the Military Police. Marlo sorrowfully notes that he had been forced to tell her that he misjudged her as a person, appalling the other soldiers.
Later, the night before they leave for Wall Maria, Marlo gets into a debate with Jean over his place in the Scout formation. He does not understand why the recruits are not placed in the vanguard where they would have the most opportunity to learn. Jean informs him that if they treated their recruits like cannon fodder they would die before they have a chance to learn. That is why Marlo is assigned to the rear.
Marlo, along with other soldiers from the scouts, takes part in the operation to retake Shiganshina District. He and the other recruits enter Shiganshina on foot while the rest of the soldiers use their ODM gear to make their way on top of the Wall. They are ambushed by Beast Titan, who appears with an army of Titans and throws a boulder into the side of Wall Maria, causing a collapse which blocks the scouts' entrance to Shiganshina, leaving Marlo and the other soldiers unable to enter with their horses. Marlo and his squad mates are left in charge of the scouts' horses, and are ordered to defend them from any approaching Titans.
In the ensuing chaos, Marlo quickly becomes the de facto leader of his fellow recruits, with his comrades looking to him for advice on where to tie up their horses. He is momentarily mesmerized at the sight of Titans up close, but is quickly jolted back into action, ordering his fellow recruits to move the horses while Levi defends them.
The Beast Titan begins targeting his throws at the soldiers themselves, and Levi orders the recruits to take the horses closer to the Wall, where they can use buildings for cover. Erwin joins them at the base of the wall, and informs them that, as far as he can tell, they are the only soldiers that have survived the Beast Titan's onslaught. As his fellow recruits panic, Marlo tries to keep them in line. Floch lets one of the horses get away, and Marlo tries to chastise him, but Floch argues that there is no point in protecting the horses, as no one will survive the battle to ride them home.
As Marlo begins to lose hope himself, Erwin addresses the recruits, informing them of his plan to defeat the Beast Titan. He and all of the recruits will mount a head on charge against the Beast Titan, drawing his attention by making themselves targets and firing signal flares. This distraction will allow Levi enough time to sneak up on the Beast Titan and slay it. Although the recruits are terrified, they are steeled by Erwin's words and take part in a suicide charge against the Beast Titan led by Erwin.
Though Marlo survives the first barrage of rocks thrown by the Beast Titan, he prepares for death when he sees the second wave coming for him. At this moment, he thinks about the enthusiasm he had for this mission, and wonders what Hitch is doing right then. He theorizes that she is probably still sleeping at that time but then stops himself and wonders why this is coming to mind at such a moment. Before he can finish his thought, a rock obliterates the right side of his head and kills him.
During the debate between Levi, Mikasa, and Eren over who should receive the Titan injection, either Erwin Smith or Armin Arlelt, one of Marlo's comrades named Floch mentions Marlo as one of the soldiers killed by the Beast Titan's barrage of rocks.
At the ceremony commemorating the Scout Regiment's success in reclaiming Wall Maria, Floch speaks to Hitch about Marlo's character. Floch praises Marlo for his encouragement in the battle, but adds that he must have regretted ever going in the end.
When Hange decides to oppose Eren's plan to destroy the world beyond the Walls, Marlo is one of the soldiers remembered while Hange tries to convince Jean and Mikasa that their fallen comrades would not support destroying the world.
His exact abilities were not shown, but presumably, he was skilled enough to gain entry into the Military Police Regiment.
- Hitch Dreyse - Marlo did not expect much of a serious attitude from Hitch, since they were quite the opposites to each other. Marlo was a serious and passionate person whereas Hitch is carefree and laid-back and would often tease him for his righteous morality. Despite this, Hitch has exhibited deep care for Marlo as when she furiously attacked Jean when the latter was threatening him and later tried to dissuade him from joining the Scout Regiment on the mission to retake Shiganshina, fearing for his safety. In Marlo's final moments, he thought of Hitch and questioned his thoughts.
- Jean Kirschtein - Although not much of an in-depth relationship between the two was shown, Jean acknowledged that Marlo acted very alike to him and they got along quite well.