History Manga / SeraphOfTheEnd

* BisexualLoveTriangle: Yu's male childhood friend Mika and female squad leader Shinoa have both admitted to love him. Yu's feelings aren't explicitly stated, but he's much closer to Mika than Shinoa. [[spoiler:It comes to a head when Guren forces Yu to choose between saving Mika or bringing back the humans who died in the past eight years. Yu instantly chooses Mika and abandons the squad, even ignoring Shinoa's confession while at it. Shinoa understands that Yu has rejected her and will always put Mika first, so she decides the only way she can get Yu to look at her is by [[MurderTheHypotenuse killing Mika]].]]

* DuelingMessiahs: [[spoiler:Yu and Guren, starting from chapter 117. Guren wants to bring back the dead humans who were killed in the catastrophe that he triggered eight years ago, but in exchange, he needs to sacrifice the lives of all the vampires and the First Vampire's son, Mika. Yu rejects Guren's plan and deserts his side because he wants to keep Mika at his side and come up with his own plan to save ''everyone'' without sacrificing Mika or anyone else in his place. Yu recognizes that the path he has chosen will require him to make harsh choices like Guren and he might even have to harm and kill innocents to achieve his goal, but [[UtopiaJustifiesTheMeans still decides to go through with it since he plans to revive the people he killed later]].]]

* FantasyKitchenSink: We have vampires, demons, angels, horsemen of the apocalypse, cursed weapons, supernatural human experimentation, and superpowerful magical religious organizations.

* HeroesPreferSwords: To no one's surprise, the main protagonist Yu ends up with a sword for a weapon.
* HideYourGays: Yu and Mika call each other family, since they came from the same orphanage and grew up together in Sanguinem, but their relationship sure seems to go way deeper than familial love because of their absolute devotion to each other and {{Luminescent Blush}}es during and after their [[KissOfTheVampire blood-drinking scene]]. [[spoiler:Eventually, Mika gives a DyingDeclarationOfLove to Yu and in his [[LotusEaterMachine ideal illusionary world]], it's shown that his deepest desire is to raise orphans together with Yu while Yu promises the two of them will be together their entire lives. As for Yu, he makes abundantly clear that he wants nothing but a life with Mika at his side and at one point, violently rejects Mika's suggestion for him to give up on him and move on to marry and have kids with Shinoa, because Yu would choose to die with Mika over even trying to start a new relationship with someone else.]] When outright asked, the author doesn't confirm nor deny Yu and Mika can be seen in a romantic light.

* MistakenIdentity: Something that turns the entire series on its head. [[spoiler:It’s revealed that Yu is ''Mikaela'' (Sika Madu’s son) ''all along'', and what everyone else thought was Mikaela was in fact the Yu homunculus inhabiting his corpse. Mikaela put his soul in Yu’s body and then modified his own memories so the ruse wouldn’t be discovered. ''No one'', except for Yu and Mika realizing it later on, not even Sika Madu, is aware of this, explaining why the plans revolving around them failed - the one they were focusing on reviving and the intended sacrifice for said revival were the opposite from the beginning, rendering said plans moot from the start.]]

* PersonalitySwap: As children, Yu was rather cynical of those around him while Mika tended to be the optimist. After being separated, Yu gains close kinship with other humans who have all experienced loss and who are all fighting to protect humanity and in the process grows a lot kinder and optimistic, particularly after learning that Mika is still alive after years of believing him to be dead. Mika on the other hand spent the 4 years separate from Yu among vampires, himself a partial-vampire who constantly thirsts for blood. He has not gained any move love for vampires even after becoming one of them, but he has learned that higher ups in the human army have rather evil plans, which has caused him to become distrustful of humanity as well. All in all, Mika has become a ''very'' cynical person, with Yu being the one thing he still believes in. [[spoiler:Later revealed to be almost literal - while their personalities were because of their upbringings, it turns out that Yu's body has Mika's soul and vice versa, and they've been calling each other by the other's name because they had no idea.]]

** The person Krul Tepes has been searching for for centuries is Ashuramaru, her brother, with the latter’s true name being Ashura Tepes.

** [[spoiler:Yu is an artificial human, having many clones of himself being created and grown in canisters by the first progenitor since [[ReallySevenHundredYearsOld thousands of years ago]]. And later on, it’s revealed he’s actually a homunculus created by Sika Madu initally as a companion for Mikaela, and later on to create humans instantly for his plan, whose mind/soul was placed into one of said artificial humans.]]

** Mika is [[spoiler:Sika Madu’s son, and the energy gathered in the seven sinful keys can either bring back all of humanity killed in the apocalypse or Mika alone.]]
** Adding onto that, what happened between [[spoiler:Sika Madu and God. It turns out all of the vampires were angels thousands of years ago living in an advanced city and journeying to reach God. Sika Madu attempted to revive his comrades from death, a sin that combined with creating life (Mikaela) lead to God killing all of the angels, destroying the city and cursing him to be undying. He created humans afterwards and placed his comrades’ souls in them in a plan to eventually fully revive everyone that died.]]
** And the biggest one so far, explained further under MistakenIdentity: [[spoiler:It turns out that Yu and Mika were in fact the [[PersonalitySwap opposite identities from the start]] - "Yu" is Mikaela, and Mika is the Yu homunculus. Their souls inhabited each other’s bodies. Further on that, the sinful keys were combined in Mikaela’s corpse, but split apart and scattered into seven pieces to delay Sika Madu’s plan of revival.]]

* SpannerInTheWorks: And how, being revealed late in the story to be the ''true'' reason Guren and [[spoiler:Sika Madu’s]] plans failed, without them even knowing. [[spoiler:Yu and Mika having each other’s souls. In reality, the only ones aware of this were Mikaela (the planner) and Yu (who agreed to work with him) - but they modified and erased their own memories so that there was no way for it to be discovered. Everyone, including Yu and Mika themselves, believed that Mika was Mikaela and Yu was the artificial sacrifice created for Mikaela’s revival. The two boys only realize it after diving deep into their own memories over thousands of years ago, with no one else the wiser, yet this is one of the main reasons the revival plans for Mikaela never worked, with everyone believing Mika was the one with the soul to be revived and Yu was the sacrifice for it.]]

* WhamLine: [[spoiler: '''Yu''': I am Mikaela. But if I’m Mikaela, ''(points at Mika)'' who’re you?]]

** [[spoiler:Yu is an artificial human, having many clones of himself being created and grown in canisters by the first progenitor since [[ReallySevenHundredYearsOld thousands of years ago]]. And later on, it’s revealed he’s actually a homunculus created by Sika Madu to create humans instantly for his plan, whose mind/soul was placed into one of said artificial humans.]]

* PersonalitySwap: As children, Yu was rather cynical of those around him while Mika tended to be the optimist. After being separated, Yu gains close kinship with other humans who have all experienced loss and who are all fighting to protect humanity and in the process grows a lot kinder and optimistic, particularly after learning that Mika is still alive after years of believing him to be dead. Mika on the other hand spent the 4 years separate from Yu among vampires, himself a partial-vampire who constantly thirsts for blood. He has not gained any move love for vampires even after becoming one of them, but he has learned that higher ups in the human army have rather evil plans, which has caused him to become distrustful of humanity as well. All in all, Mika has become a ''very'' cynical person, with Yu being the one thing he still believes in. [[spoiler:Later revealed to be almost literal - while their personalities were because of their upbringings, it turns out that Yu's body has Mika's soul and vice versa, and they've been calling each other by the other's name to unknowingly maintain that ruse.]]

* PersonalitySwap: As children, Yu was rather cynical of those around him while Mika tended to be the optimist. After being separated, Yu gains close kinship with other humans who have all experienced loss and who are all fighting to protect humanity and in the process grows a lot kinder and optimistic, particularly after learning that Mika is still alive after years of believing him to be dead. Mika on the other hand spent the 4 years separate from Yu among vampires, himself a partial-vampire who constantly thirsts for blood. He has not gained any move love for vampires even after becoming one of them, but he has learned that higher ups in the human army have rather evil plans, which has caused him to become distrustful of humanity as well. All in all, Mika has become a ''very'' cynical person, with Yu being the one thing he still believes in. [[spoiler:Later revealed to be almost literal - while their peronalities were because of their upbringings, it turns out that Yu's body has Mika's soul and vice versa, and they've been calling each other by the other's name to unknowingly maintain that ruse.]]

* PersonalitySwap: As children, Yu was rather cynical of those around him while Mika tended to be the optimist. After being separated, Yu gains close kinship with other humans who have all experienced loss and who are all fighting to protect humanity and in the process grows a lot kinder and optimistic, particularly after learning that Mika is still alive after years of believing him to be dead. Mika on the other hand spent the 4 years separate from Yu among vampires, himself a partial-vampire who constantly thirsts for blood. He has not gained any move love for vampires even after becoming one of them, but he has learned that higher ups in the human army have rather evil plans, which has caused him to become distrustful of humanity as well. All in all, Mika has become a ''very'' cynical person, with Yu being the one thing he still believes in.

* MistakenIdentity: Something that turns the entire series on its head. [[spoiler:It’s revealed that Yu is ''Mikaela'' (Sika Madu’s son) ''all along'', and what everyone else thought was Mikaela was in fact the Yu homunculus inhabiting his corpse. Mikaela put his soul in Yu’s body and then modified his own memories so the ruse wouldn’t be discovered. ''No one'', except for Yu and Mika realizing it later on, not even Sika Madu, is aware of this, explaining why the plans revolving around them failed - the one they were focusing on reviving and the intended sacrifice for said revival were the opposite from the beginning, rendering said plans moot from the beginning.]]