- "This is a warning. Due to the foolish acts of humans, a deadly virus has spread. Unfortunately, the human race will perish."
- —The annoucement
One day, a mysterious virus appeared that seemingly killed all humans over the age of thirteen, and vampires suddenly emerged taking the surviving children underground.
A few years later, Yūichirō Hyakuya and Mikaela Hyakuya live there and give their blood. Yu hates the vampires and gets into trouble with them, but Mika gives his blood to Ferid Bathory in exchange for good food and anything he might want. That night, they eat the curry Mika earned and decided to escape.
During the attempt, Ferid slaughters their entire family. Yu is the only one to escape having to leave Mika behind. He flees to the surface and runs into Guren Ichinose, who calls Yu a guinea pig and says he will use him to defeat the vampires.
As an aircraft can be seen flying over a city adorned in lights, as people are seen going about their days; walking through the city on chilly winter night. Among this crowd of humans a duo of adults can be seen walking side by side, until one of them seemingly vanishes leaving the other confused. Taking in her surroundings, the girl looks around for the man only to see him lying on the ground. Beginning to approach the latter, she suddenly clutched onto her chest, gasping for breath eventually joining the other on the ground, coming face to face with an unexpected death. The other adults can be seen following suit as a car crash occurs, and the plane crashes on to the ground; all of them now having collapsed with the society the world had known until today.
Among the renaming ashes of a big chunk of humanity, third Progenitor: Krul Tepes, is leading a her faction of Vampires, as she strides down the streets of Tokyo, taking in the aftermath of the events that had just taken place.
Through the chaos emerging due to the sudden disappearance of adults, group of kids lead by Mikaela Hyakuya can be seen running through the streets, with the animals such as dogs barking, clearly terrified too. Seeing an active source of light Yūichirō Hyakuya comes to a halt, only to witness a man vomit out blood and pass away right in front of him. As his mouth falls open in shock, he sprints to catch up with the others.
Continuing to run for their lives, they can hear an announcement beginning to explain what exactly had happened. It spoke of a warning to the rest of the human race, blaming their foolishness for the spread of the virus, saying that it was only inevitable that the entire race would perish.
Directing them to a play room Mika slams open the door only to see the orphanage director lying on the floor, as Akane Hyakuya points out his condition. Taking in the situation, Mika tells Yu to look after the others as, as they are trying to reach out to the director. The announcement goes onto say that children under the age of 13 would not be infected by the virus, confirming that they, the direct unit of Krul would start "protecting" the children in the district. Watching a shadow go across his face, Yu moves his gaze along to window where a vampire can be seen shattering the glasses with extreme ease, as he walked in. Much more terrified than, the kids now huddled together in a corner. As the door opens once again, another vampire walks in.
On the highway, above the river that now looks like it's flowing rich with blood, a number of green trucks can be seen carrying children, Yu and Mika among the lot. Sitting close together, Yu looks down at a smaller boy, who trembles against his touch.
Four years later, over the eerie scene of the Sanguinem, a young children are seen forming lines, walking out of a tunnel like system, waiting behind some sort of a barricade. Moving ahead, Yu can be seen confirming his identity and moving forward in line waiting there for Mika, who also had to confirm his identity. After he's done, he can be seen walking to the same place as Yu as they venture up a flight of stairs.
A girl can then be seen, sitting down as a pipe is inserted into her neck, drawing her blood. Looking weaker, Yu walks with his hand around Mika's shoulder, after which the latter can be seen sitting down on a flight of stairs as he drinks a liquid from a bag. Clearly not pleased with the taste Mika scowls as Yu grunts, crushing his packet. Concerned, Mika asks Yu if he would be drinking it or not, as Yu simply sits down beside the other, looking at the drink in hand. Yu affirmed that could not drink this "disgusting piece of crap". Mika looked at the other as he said that Yu's palette was extremely gourmet, as the man in question looked away in retaliation. Yu goes onto say that Mika should stop doing everything that they said. Face going grim, Mika stands up and to say that it wasn't that bad. Yu, taken aback exclaimed and asked the blonde if he was serious. Mika plainly said that they wouldn't be killed in there and they could live with their family; asking Yu about that not being enough, as he proceeds to toss the packet in the bin. Egging on the argument, Yu said that he was not their livestock, throwing his packet at Mika (who easily dodges) when he told him not be so stubborn.
As the packet falls on the ground two children could be seen drawing on the floor. Noticing the situation Yu calls out as a pair of hooded vampires approach and walked straight into the children; one stepping on one child's hand while the other kicks the second out of the way. Enraged, Yu attacks one of them, who dodges with extreme ease as Mika apologizes on the latter's behalf trying to explain how Yu is "messed-up in the head" as he tried to think of a possible excuse for the Yu's actions. As Yu still continues struggling, the vampire now holds Yu over the edge of the walkway, ready to drop him at any given moment. Mika visibly panics.
As Yu's life hangs in the balance, he looks down at the clearly long fall, as the vampire puts his hand out; fully concentrated only to be disrupted as seventh Progenitor and noble; Ferid Bathory as he makes his grand entrance, greeting the lot. The vampire holding Yu over the ledge finally tosses him back onto the walkway before taking his leave as the latter began gasping for air in a coughing fit due to being held by his neck. Yu, now curious questions if Ferid was a noble, only to be proven correct as Mika cheerfully runs up to him greets the vampire, calling him Lord Ferid. Walking closer, Ferid greeted Mika in return, asking if everything was okay, and Mika simply said it was nothing and one of his family members was just causing some trouble, to which the former told Mika that he had too much to worry about. Moving in even closer, Ferid strokes Mika's cheek asking him if he would like to come by his mansion tonight as Mika nods, saying yes please. Ferid calls him a "good boy" saying that he had delicious blood and was always very much welcomed there. Now looking over at Yu, he asked if he would be joining them too, beginning his reply with a clear no, Mika cuts the former off by saying he's too shy, and maybe he could tag along next time. Ferid shrugs it off saying that was too bad.
Now pulling Yu along, him and Mika can be seen walking down a corridor, as Ferid lets out a soft chuckle and walks away. Walking side by side, Yu had asked Mika about why he had apologized, saying that he was about to kick that guy's butt. Mika sighed and looked at Yu, looking extremely used to this, saying there went the latter with his nonsense again, additionally saying there was no way a human could beat a vampire. Yu managed to retaliate by saying that they'd never know until they tried. Mika again said that it was not possible, telling Yu to not overwork himself, additionally saying it was an extremely close call. Stopping in his tracks, Yu turns back to Mika asking the latter if he and Ferid knew eachother, and he indirectly responded by asking if it was important, additionally saying that if her offered his blood to thee noble, he would give the blonde whatever be wanted; including good food and to survive in a place like this, they had to use their heads and be smart. Yu now walks up to him giving the other a gentle punch on his face and walking away. Holding his hand against his face, he asks Yu if there was something he wanted, but the latter simply cut him off before be could finish, saying a no. Mika is now left staring at Yu as the other walks away.
Eventually, Akane finds Yu pouting on a rooftop. She asks him why he isn't with Mika and tells him that their family is waiting for him to come back, so they can eat dinner. Yu remembers his time back at the orphanage, where the director introduced him to Mika and the other orphans. He comes in, and Akane is preparing curry for all of them. The children are all so excited that they began saying its their birthday. Akane reminds them all to be sure to thank Mika later. The children dig in, but Yu refuses to eat, knowing what was involved in getting it.
That night, Mika returns quietly into their house, Yu hears his creaking on the floorboards. They chat briefly, Yu says he will give his blood next time but Mika insists that no one wants his nasty blood. Mika breaks into tears for a moment when he tells Yu that Yu gives them hope. Then, they go back downstairs, and Mika serves some curry for himself. He puts some of his plate into a separate bowl for Yu. Yu insists he does not need it, but Mika already realized Yu did not eat any earlier. He gives Yu the gun he stole from Ferid and tells Yu to build up his strength. They chat, and Mika suggests that they escape from this world.
Akane hears them and comes down the stairs to see what they were doing. Excited, Mika pulls out the map that he stole and tells Akane to wake everyone up.
The children sneak through the sprawling underground city. At one point, a vampire guard hears them, but they hide in a grate and managed to avoid detection.
They come into view of the exit of the city and walking with the assurance that they have made it, Ferid steps out from beside the gateway and basks in their expressions of shock and disbelief. He comments about how he loves this game and then proceeds to slaughter the children one by one.
Akane is murdered, leaving only Yu and Mika alive. Mika takes the gun back and charges at Ferid, who pierces Mika through the chest with his hand. Mika raises the gun at Ferid's face, but Ferid slices off Mika's arm. Mika tells Yu to run, however, Yu catches the gun and shoots Ferid in the head.
Yu cries as Mika falls to the ground. Pulling Mika to him, he tries to drag Mika to the exit but falls. Mika pushes him away, not wanting them all to die as other vampires have arrived. Crying and covered in Mika's blood, Yu races and stumbles as he escapes the underground.
It is night as he runs outside into the snow, but he can see a ruined human city before him. He struggles and is eventually come across by Guren Ichinose and his aides, Shigure Yukimi and Sayuri Hanayori.
Guren calls him a guinea pig of the Hyakuya orphanage and tells him he will be useful for fighting the vampires. Yu cries and says that's what he wants. He hugs Guren so tightly that he eventually knocks Guren over leaving him baffled.
Four years later, 16-year-old Yu walks the ruined streets above ground in his military clothing.
Differences with the manga
|The manga starts off with Yu reading a book about vampires.||The opening scene features a city. Seconds later, chaos erupts.|
|Mika beats Yu up when they first meet. He also tells Yu about his own past, and many of the younger children also join in.||These were not shown in the anime.|
|Hyakuya children are with the director when she collapsed.||Yu, Mika, and a few others were outside and went back into the orphanage when they discovered the director had collapsed.|
|Not in manga.||Additional scene: the vampires meet the Hyakuya children above ground.|
|The livestock are barefoot.||The livestock wear slip-on shoes.|
|The children were taken to Sanguinem, the vampire capital.||The name of the city was not mentioned.|
|Sanguinem seems to be located on one level.||The vampire city has numerous bridges and walkways|
|Not in manga.||Additional scene: the children are checked off before giving their blood where Yu and Mika are named.|
|Although Yu curses at the vampires, they just ignore him.||Additional scene: children draw with chalk on the walkway, and Yu takes issue with some vampires actions. He gets physical with one, who nearly drops Yu over the edge.|
|Their home is only a flat and bare room without furniture.||The home the Hyakuya children live in underground looks like a beaten house with a second floor. It is dusty and dirty with cobwebs. It has drawings by the children in it, including one each of Yu, Mika, and Akane.|
|After being at Ferid's, Mika appears at the doorway, and blood could be seen on his neck. When he loses composure and drops a few tears, Mika says he is just kidding.||Mika peeks at the children over a ladder and no blood is shown on his neck.|
|Yu eats the curry off-screen and tells Mika it is good and that the children loved it. Mika never eats the curry because they leave right after he gets home that night.||Yu refuses to eat the curry until Mika joins him.|
|The manga transitions to the Hyakuya family arriving near the exit.||Additional scene: a vampire guard hears some of the children while they try to escape, but the children manage to hide.|
|The children talk about how they are geniuses and are not livestock when they reach the exit.||These were not shown in the anime.|
|When the kids arrive to the end of their escape plan, Ferid reveals himself at the top of the exit.||Ferid appears from beside the exit.|
|Not in manga.||Yu shoots the gun into the air when the children hesitate to run in order to get them to escape.|
|Ferid only lightly punctures Mika's chest with his nails.||Ferid pierces his hand completely through Mika's chest.|
|Not in manga.||Additional scene: Yu drags Mika with him for a few feet and becomes covered with his blood before he escapes.|
|Yu walks out into the morning sunlight and stumbles onto grass, and he wonders why the world was not destroyed and is angrier. Guren is waiting with Shigure and another soldier.||Yu steps out into winter and snow during the night in the anime. Guren is with Shigure and Sayuri. Yu is too heartbroken and distracted that he hugs Guren.|
List of characters in order of appearance:
Anime images provide a visual overview of the events of Episode 1 with depictions of the characters, Seraph of the End world, scenarios, artistic style among other areas.
|Episode 1 • Episode 2 • Episode 3 • Episode 4 • Episode 5 • Episode 6 • Episode 7 • Episode 8 • Episode 9 • Episode 10 • Episode 11 • Episode 12 • Episode 12.5 • Episode 13 • Episode 14 • Episode 15 • Episode 16 • Episode 17 • Episode 18 • Episode 19 • Episode 20 • Episode 21 • Episode 22 • Episode 23 • Episode 24|