Manga by author Ohtaka Shinobu

.Fourteen years ago, mysterious buildings called "Dungeons" started to rise in various places around the world. Within these dungeons, powerful beings called djinns rule over. When a person successfully conquers the dungeon, the djinn offers their immense strength in the form of Metal Vessels, recognizing him or her as a worthy king candidate. Adventurers from many empires and kingdoms venture into the dungeons in search of their bountiful treasures and the power of djinns. However, to travel through them is not an easy task, and only Magilegendary magicians who choose kings and develop countriescan guide people through.After being trapped in a room for most of his life, a young Magi named Aladdin finally sets out on a journey to explore the world along with his friend, a djinn named Ugo, who he can summon from his flute. Through a series of fateful encounters, Aladdin meets new various friends and allies, and together they begin an adventure that will change the fate of the world.[Written by MAL Rewrite]

It tells the story of Sinbadearly life, when he captured the first Dungeon, Baal.

In a world similar to that of Scheherezade's tales, a mysterious young boy named Aladdin drifts from place to place with his djinn Ugo. Ugo lives inside a golden recorder, and Aladdin is on the hunt for his true container "The Djinn's Metal Vessel". One day he encounters Alibaba, a poor lad determined to enter one of the mysterious Dungeons that popped up a decade ago in order to make his fortune. Thus the the two begin their adventure in a Persia that never was.

Koushi Inuzuka is heir to an ancient family tradition of powerful martial arts. Unfortunately for his father, Koushi wants absolutely nothing to do with such dangerous things. His goal is to become an avenging prosecuting attorney, turning him into a bookworm that his father simply can't understand. Still, Koushi finds a great deal of comfort both in his studies and in the structure of law.Until the day that Momoko Kuzuryu, daughter of another great house, drops into his life and demands that he, the last scion of the strongest family of bushido martial arts, sire a baby with her.From that moment on, Koushi is forced to think and act faster than ever before as ever-stronger opponents appear to challenge him. The race to stay alive hinges on unlocking memories from his suppressed past and, possibly, unleashing his forgotten physical courage. And somehow, at the center of all those memories, stands Momoko.How can a wimpy bookworm survive the attention of skilled assassins for long? Then again, his opponents are discovering that some forms of strength have nothing at all to do with muscles or techniques...