ZERO: Dragon Blood is the spin-off series of Garo and continues after the events of Black Blood.
Centuries into the past, before the age Makai Knights, there was only the Makai Priests. In an era where humanity struggled to survive against the terrible carnage of the Horrors, there were those that would offer human sacrifices to their predators to prolong their survival. Once such sacrifice would be an infant of his own clan. Ready to be devoured at the sacrificial altar for the Horrors, fate would intervene and save the child from death and made into a Dragon Knight.
A Makai Dragon witnessed the sacrificial ritual and intervened to save the infant. Raising the child as his own, he would name him Edel. Through their trusted bond, the wise dragon educated Edel in the art of survival, language, and culture. It was this trusted bond that the dragon granted him powers as a Dragon Knight, giving him dragon-like abilities as well as making him the strongest warrior in the lands. However, his reign wouldn’t last. His parental dragon had died, but in his place was a dragon egg, a new dragon and companion for Edel, Nova.
For a while, the duo would use their powers to slay Horrors across the land and became the new champions of humanity against Horrors. Although still human, Edel wasn’t motivated to be with humanity and identified himself as a dragon. Through a life-long bond, Edel and Nova became mates and Nova produced a dragon egg, making Edel the father. Unfortunately, their lives were ruined because of the humanity.
A group of Makai Priests know of Nova and Edel and coveted their powers. The priests kidnapped a weakened Nova and attempted to kill her to exploit the powers of a dragon. However, Edel intervened and attempted to save Nova; he was losing. Unwilling to allow Edel to die, Nova broke free of her bonds, sealed Edel away in a dragon shell, and scorched everything to cinders. She would die in her weakened state, but not before her remains transforms into a great forest, where their child will be protected in the seclusion of the forest.
About a decade before main events, Alice Hiromi, an orphaned girl, lived a harsh life. She was bullied and alone, but she had an appreciation for the beauty of things. One day, she discovered the surviving remains of Nova’s nest, with the Dragon Egg still resting there, undisturbed for centuries. When Alice touched the egg, she had a vision of a world purified by fire and reborn beautiful once again. From then on, she became the egg’s minder, always watching over it and tending to it until it was rediscovered by the Makai Order. Makai Priests came for the egg and Alice tried to fight them, but she was only a little girl and didn’t have the power to fight off the adults; the priest got the dragon egg and had it locked away in a tomb for safe keeping. However, all will change with Edel’s return.
In modern times, Okina (older brother) and Kagome (young sister) are a duo of sibling priests that sought a means to become stronger. One day, while researching, Okina found the tome that spoke of the legendary Dragon Knight and Makai Dragons. In the interest of making Kagome more powerful, Okina stolen the dragon shell that held Edel. Kagome didn’t agree with the plan and fought against Okina, but he managed to distract Kagome long enough for him to release Edel out. Still angered for what humanity had done to him and Nova, when Okina asked for his power, Edel killed Okina as his reply. Kagome tried to take on Edel, but she was no match and was thrown aside. Edel begins his search for his long lost child (dragon egg), however, another also seeks for it as well.
Since losing the dragon egg, Alice has never given up on reuniting with it. As soon as she was old enough to leave the orphanage, she made it her life quest to recover the egg. Through her own research into ancient books, she learned about the makai realm and the people involved. She also discovered literature about the dragon egg’s whereabouts and realized she can attain it through the power of a Makai Knight. Through the use of a Makai Compass, Alice sets her plans into motion.
After the events of Black Blood, Rei has moved to Rune City along with Master Barkeeper and Makai Priest Bakura of The Lupo Bar. It was while investigating a hotel, a Horror den, that Rei rescued Alice. However, it was Alice’s ploy to get closer with Rei and his group. It wasn’t long that Rei received orders that Dragon Knight Edel was loose and needs to be neutralized. Alice has also made herself home in a spare storage room right upstairs of the bar, much to Rei’s dismay.
While attending to the guarded tomb of makai relics, Rei was reunited with Makai Priestess Rekka and Edel appeared, killing whoever stands in his way. Alice manage to find her way to Rei’s location and she finally reunited with her egg, however, Edel was also there to reclaim it. Rekka prepared a special magical container to seal the egg, but Edel’s appearance prevented it from finishing. It was while everyone was busy fighting over the container that Alice managed to attain it and she used her hand to activate and seal the egg. Edel managed to retrieve the container and fled the scene with it, but he’s unable to open the sealed container without Alice.
Alice is now the living key to unseal the magical container and Rei's group intends to have Alice protected. However, being trapped in a bar all day has its boredom and despite being watched by Bakura, Alice found inventive ways to escape her “house arrest” to enjoy some sightseeing and photographing. Rei ultimately became Alice’s minder and Rei started to feel attracted to Alice. It wasn’t long that Kagome appeared and attempted to kill Alice, believing if Alice dies, then Edel can never regain access to the egg. However, Rei stopped her and Rekka convinced Kagome to back off.
It was while feeding Kagome that she told everyone of her background story and her mission to stop Edel. Kagome made assurances that she’ll never attempt to kill Alice and even protect her. Knowing that Edel would come after Alice to help him unseal his egg, Rekka placed a protective charm on Alice to prevent Edel from finding her, but Kagome intentionally neutralized the charm to bait and lure out Edel. Unfortunately, Kagome’s plan didn’t work out too well as Edel revealed himself in broad daylight and easily kidnapped Alice without resistance.
It was while being captured that Edel convinced Alice to release the egg so the egg may have the chance to be hatched. Rei, Rekka, and Kagome managed to find Alice and aided in her rescue. Alice ran away with the unsealed egg while the trio fought off Edel. Things came at a close when Kagome decided to sacrifice herself to take down Edel. Kagome created a magical explosion and Kagome died falling to her death, but so did Edel. Kagome’s attack burned a hole through his chest and he too fell to his death. With Edel dead, the team helped buried Kagome and the group awaited on the Order’s decision on what to do with the egg.
It was while waiting for the higher-ups to make a decision that Rei attempted to get rid of Alice. Rei didn’t want Alice’s involvement with the makai world and Alice did eventually relent to moving away. Unfortunately, by the time orders came through to destroy the egg, Alice already left and absconded with the egg. It wasn’t long while admiring the egg that the dragon finally hatched.
Alice named the baby dragon, Loop. Because Loop sees Alice as its mother, Loop has a strong attachment to Alice. Rei managed to find the remains of the hatched egg and was very concerned for Alice as even a baby dragon can be very dangerous. Because Rei had to deal with a Horror threat, Rekka volunteered to help search for Alice and Loop while Rei handles the new Horror. Rekka found Alice and tried to convince her to hand over Loop, but she refused; Rekka attempted to magically take away Loop, but the dragon had the ability to nullify Rekka’s magic and ran off with Alice.
While running away from Rekka, Alice bumped into Rei as he fought off a Horror. With the double-team effort of Rei and Rekka, the duo managed to defeat the Horror, but its insectoid collective of Horror bugs lived and went after Alice. Ready to protect its mother, Loop roared and even its baby sonic cry was strong enough to stop the insects. With a concentrated blow of dragon fire, Loop was able to wipe out all the insects with a single blow. However, Loop was weakened from the process and both Alice and Loop was mysteriously teleported away.
In the middle of the woods, Alice found Loop dying. Loop used all of his power to save Alice, but weakened him. Unsure what to do, Alice tried to feed him water and blood, but nothing worked. It wasn’t until Edel revealed himself that he explained that Loop needed makai energy to recover. Edel survived his battle and has been in hiding. He revealed himself to Alice to help Loop. Adel took Loop to an ancient water source that’s connected to the makai realm to help Loop absorb makai energies to recover and become a full grown dragon. Edel took the time to explain his past and his reasons for despising humanity. However, before all can be explained, Rei and Rekka appeared to fight.
Alice resisted Rekka and Rei, believing the duo would either cause harm to Loop or separate her from Loop. It was enough of a distraction for Edel to escape with Loop in tow. Edel would find an abandoned industrial facility to help Loop complete his metamorphosis. Back in the woods, Alice insisted on following Rei and Rekka to locate Loop, but the two refused due to her attachment to Loop. To make her go away, Rekka kissed Ray to suggest what they feel for each other wasn’t real. Hurt that Rei would kiss Rekka, she ran off. Once Alice ran away, the duo could finally hunt for Loop without distraction.
By the time Rekka and Rei found Loop, the dragon has become a fully grown dragon now. The duo attempted to stop the dragon, but it was too powerful to be stopped. Edel at first thought Loop was loyal to him, but he was terribly surprised to find out Loop would take a whole bite of his body while Rekka was tied down from Loop’s tail and Rei pinned down by Loop’s foot. Just as things might turn for the worse, Alice sensed Loop and found him. She told the dragon to stop, letting all parties free. Although a powerful beast, Loop remains loyal to Alice and the two ran off. Not willing to allow a dragon loose in the public, Rei gave chase while Rekka handled Edel.
Edel has been weakened in his battles, Rekka was able to defeat him in battle and rejoin Rei to take on Loop. It was while Rei was trying to talk sense to Alice that she revealed everything played out according to her ploy. It reveals Alice’s twisted desire to see a beautiful world after Loop burns it all. Rei was saddened by the truth, but with Rekka’s help, Loop was temporarily defeated. Alice realized Loop wasn’t at his full potential and needed more power; she bonded with Loop and now she’s a part of Loop. Believing Alice sacrificed herself, Rei wanted to personally end things, but was surprised Alice resurfaced as a Dragon Knight.
It was really a fake copy. Loop made a Dragon Knight version of Alice to fend off Rekka and Rei as he builds up the energy to grow his wings. Rekka was severely injured when Fake-Alice stabbed her in the back and leg and Rei was forced to fight alone. When the Fake-Alice was defeated, Loop grew his wings and flew off and Rei gave chase. Too injured to go anywhere, Rekka remained at the previous battleground until Bakura showed up to help heal her injuries.
At Alice’s favorite view spot of Rune City’s statue, Loop landed there and started to fully charge himself. Opening a part of his head and expanding his body, he began to absorb the ambient makai energies from the moon and revealed his fully powered form. As Loop got ready to charge his energies to burn Rune City down, Alice realized this isn’t what she wanted and changed her mind. Unfortunately, it was too late and Loop couldn’t stop. However, Zero charged right in with Ginga to divert the blast into the air.
Zero fought against Loop, but the dragon proved to be too powerful. Nearing the end of his armor's time limit, Loop grabbed Zero and unable to escape. Despite Silva's warnings, Rei couldn't break free and transformed into a Lost Soul Beast. As Lost Soul Beast Zero, Zero's combat strength was able to rival Loop. Lost Soul Zero began attacking and biting Loop. Any place of Loop's body that Zero bitten and tasted, Zero’s form absorbed a physical trait of the dragon. Eventually, Zero himself became a Lost Soul Dragon Wolf Zero, able to fly and attack like a dragon. Rei defeated Loop and was about to finish the job until Rekka appeared and intervened.
Rekka tried to stop Rei from finishing Loop because Alice was still inside. Magically mimicking Alice's voice, Rekka attempted to appeal to his senses. Zero was distracted enough that Loop's tail struck the armor’s core switch (near the belly) and revert Zero back to normal and released his armor. At that point, Loop died and began transforming into a forest. Rei didn’t want to give up on Alice and dived into the growing green to find Alice. Once he found her, she was also dying. Before she died, she was able to see Rei’s tearful face and remarked how beautiful it was. Rei also told Alice his true name, Ginga, and she phased away. The only surviving memento of Alice was a micro-sized dragon egg.
In the end, life moves on. Rekka returned to the Senate and Bakura continues to watch the bar while Rei resumes his lone-wolf life. At Lupo's with Rekka, Bakura was worried about Rei not coming back, but Rekka was confident Rei would return as he promised to buy Rekka a drink. On a rooftop, having a daydream, Rei ponders over the dragon egg and Alice. Rei awakens back to his reality with Silva's detection of darkness. A new Horror threat arrives and Zero answers the call.