Loretta Oratorio and Mirabelle Graceland are two thieves looking to steal an object of great power: The ARMS. They break into Alcatraz, the floating prison in the sky, and soon meet Dr. Kiel Aronnax, who escapes from imprisonment. The three try to escape, while trying to find the treasure, but instead stumble upon a mysterious ten-year-old boy named Sheyenne Rainstorm!

In hopes of finding his real body, Sheyenne, along with Kiel travel to a famous thieves' bazaar. Meanwhile, Mirabelle and Loretta go to an infamous ARMS collector in an attempt to relieve him of his collection. When their plan fails, the two bandits decide to steal Sheyenne’s weapon to sell it!

Sheyenne, Kiel, and Isaac come across a village plagued by a Sand Dragon who guards a treasure. Sheyenne hears rumors that the treasure being a body, and hoping that it may be his, the trio take on the task of killing the dragon and rescuing Machela, who believes that the dragon is actually her dead fiancee! Will they be able to accomplish their mission? Is the dragon really Machela’s fiancée? And, is the treasure really Sheyenne’s body?

In hopes of finding Sheyenne's missing body yet again, Sheyenne and Kiel travel to the fortress library, Libra, after hearing word of an unidentified, charred body. However, Loretta and Mirabelle have also arrived in the great library in hopes of stealing a book that once belonged to the Evil Race; the valuable Faluna Bible. What the gang doesn’t know is that they have all arrived in the midst of a crisis...

Loretta and Mirabelle attempt to cash in on the inheritance of Rotes, a deceased painter, by boarding a ship to attend the reading of the will and "borrow" a few of his paintings. Sheyenne and Kiel also show up looking for Sheyenne’s real body. As the mysterious life of the painter is revealed, the four will, once again, become part of a huge fiasco

Sheyenne, Kiel, and Isaac finally reach their destination - Sheyenne's hometown of Parskiarka. When they arrive, they discover a city total emerged under water! As he looks around, he finds a woman named Laila Lie, whom he dream about the previous night. Why is Laila? What connection does she have to the evil race? And, can Twilight Twilight Venom truly destroy a town?

Laila is abducted by several strange scientists who dwell at the bottom of a lake. Sheyenne prepares a daring rescue to save her, already knowing that he is really the captors main target. Meanwhile, Loretta and Mirabelle search through the underwater ruins for a mythical sea monster that could net them 2 million gala if they can just get a photo of it.

As a young boy dies, his final wishes are for Sheyenne, Kiel and Isaac to take care of a baby Crimson Noble, a Noble Red. The three set out to return the baby girl, whom Isaac names Faluna, to her parents. They soon encounter Mirabelle and her cousin, Tamuri (the father of the baby) and a Chinese martial artist named Pakuai whose goal is to capture and eat the baby Noble Red!

Mirabelle's family, the Gracelands, fall on to some hard times due to bad business decisions. Luckily for then, the old Count Ampire gives them money in exchange for Mirabelle's hand in marriage. The Count's chances of snagging a bride get much smaller when Mirabelle's parents get a taste of Sheyenne's delicious blood. Will Mirabelle and the others be able to get out of this inane situation!

Loretta sets her sights upon an extremely rare Crest card only to find out from it's owner, Judecca, that it's been stolen. It just so happens that Sheyenne and Kiel are guarding the supposed thief, Sybil. Sybil, who is brandishing a legendary ARMS weapon, promises to reveal the location of Sheyenne's body when they safely guide her to the next town. However, they soon learn that the men after her also have ARMS!

Sheyenne becomes deeply troubled by all the previous failed attempts to find his body. Elsewhere, ambitions stir restlessly as a woman whom Sheyenne knows claims to be responsible for his despair. She claims she helped craft a being capable of handling the ARMS!

After falling off a river's cliff, Sheyenne suffers from memory loss. Doctor Clark, a man who tends to orphans, takes him in and Sheyenne feels right at home. But when a female outlaw named Cannon and her gang come to take the doctor, Sheyenne is forced to up his ARMS to protect Dr. Clark and the kids who reside there.

Almost at their destination, Sheyenne causes them to miss their ride when he spots Laila!! Soon, part of the mystery shrouding Laila comes to light. Meanwhile, Kiel and Isaac team up with the legendary assassin Golgol 30 to fend off the men chasing Laila.

Sheyenne, Kiel, and Isaac finally arrive at their destination, but soon discover that they are wanted. As Valeria's plan is set into motion, one of the gang will betray Sheyenne.

As Sheyenne's duel with Kianu grows more and more intense, Isaac and the others learn of the secrets of 10,000 years ago!

As all of the secrets finally become unraveled, the angry goddess stirs violently with the weight of her unfulfilled love putting the entire world in peril! Dark desires give way to the second coming of Twilight Venom, and only Sheyenne and his legendary ARMS can stand against its awesome power. Can he pull it off? Or, will the world end?

Almost at their destination, Sheyenne causes them to miss their ride when he spots Laila!! Soon, part of the mystery shrouding Laila comes to light. Meanwhile, Kiel and Isaac team up with the legendary assassin Golgol 30 to fend off the men chasing Laila.

Sheyenne, Kiel, and Isaac finally arrive at their destination, but soon discover that they are wanted. As Valeria's plan is set into motion, one of the gang will betray Sheyenne.

Valeria's plan backfires on him when Laila takes center stage. Meanwhile, Sheyenne faces off against the Evil King himself, Kianu, who is using Sheyenne's body!

As Sheyenne's duel with Kianu grows more and more intense, Isaac and the others learn of the secrets of 10,000 years ago!

As all of the secrets finally become unraveled, the angry goddess stirs violently with the weight of her unfulfilled love putting the entire world in peril! Dark desires give way to the second coming of Twilight Venom, and only Sheyenne and his legendary ARMS can stand against its awesome power. Can he pull it off? Or, will the world end?