The series takes place in the Imperial Capital of 1930. A group of people known as "Jaegers" landed on Tokyo Station. They carry musical instrument cases and came to hunt vampires. A man named Yuliy stood among them with a striking serenity and unusual aura. Known as a werewolf who had his home village destroyed by vampires, he and the Jaegers engage in battle against the mysterious holy arc known as the "The Arc of Sirius". What truth awaits them?

In the year 1930, vampires have infiltrated Tokyo to feast upon its unsuspecting citizens. As the number of victims continues to rise, the city's authorities decide to hire the Jaegers—a strange, diverse group of individuals tasked by the V Shipping Company to hunt down vampires around the world. Carrying musical instrument cases to disguise their identity, the Jaegers battle the vampires with the same mercilessness demonstrated by their foes. Yuliy, the Jaeger's most skilled warrior, is the sole survivor of a vampire raid on his home village. Using the strength granted by his werewolf blood, he works with his team to assist Tokyo's law enforcement with the city's vampire problem. Though under the pretense of helping the police, the Jaegers are actually fighting the vampires over the mystical Ark of Sirius. With its power to change the fate of the world, Yuliy and his friends must locate the artifact before the vampires can use it to achieve their destructive goals.

It ain't easy being a genius... Prince Wein is ready to commit treason. And who can blame him? Faced with the impossible task of ruling his pathetic little kingdom, this poor guy just can't catch a break! But with his brilliant idea of auctioning off his country, this lazy prince should be able to retire once and for all. Or that was the plan...until his treasonous schemes lead to disastrous consequences-namely, accidental victories and the favor of his people!

The King of Natra has fallen ill, leaving the only hope for his kingdom to his son, Prince Wein Salema Arbalest. Known to be capable and wise, he is the perfect candidate to become the prince regent. However, if the prince has anything to say about the matter, he would rather sell off the Kingdom of Natra to the highest bidder! Since he wields the authority of the throne, no one can stop Wein from auctioning off the country and using the profits to retire in comfort. All he needs to do is raise the value of the small kingdom to maximize his gains. But whether Wein's grand plan will succeed remains to be seen, as his wit often surpasses even his own expectations—much to the benefit of the oblivious citizens of Natra.