12 Beast is a one-shot by Pixiv artist Takemaru "Okayado" Inui that became an ongoing manga series.The one-shot follows the adventures of General Eita Touga, his support staff Aero, and their army of mercenary monsters as they try to save the world of Live-Earth from the Gigas, massive machines exterminating the inhabitants, the Autana (the series' term for half-human monsters).With the might of their incredibly diverse troops, strengths complemented and weaknesses covered; the Gigas Slayer, a steel gauntlet that gives Eita superhuman strength and allows him to borrow Aero's power; and his PSP, tablet and a war game for any and all strategic planning, they travel across the land defending the weak and slaying the anti-Autana weapons... provided they don't die of starvation first or stage a mutiny, as said army is perpetually broke, and Eita can't resist helping the needy and poor.The ongoing tells the story of how they get there: Eita is a high school ninja gamer from Present Day Earth who'd like nothing more than to keep out of danger, until Aero, a harpy from Live-Earth, shows up to convince him to help protect the Autana, a Gigas hot on her trail.Eita inadvertantly accepts Aero's request after he trashes the Gigas, and so they set out to save Live-Earth, recruiting their army as they go (including Lamiae, Lizard Folk, Centaurs, Satyrs, Minotaurs, Kobolds, Mummies, Dullahan, Golems, Scylla, and Slimes).... oh yeah, did we mention the abundance of hot monsters and fanservice?For Okayado's other works, see Daily Life with Monster Girl and Deadline Summonner.
This work provides examples of:
The Ace: Heavily implied with Eita's brother, Kouki.
All but confirmed with the second chapter, really.
Adam Smith Hates Your Guts: Despite saving Live-Earth from the world-destroying threat of the Gigas, Eita's army STILL needs money to function properly. Food doesn't pay for itself, unfortunately.
Aloof Big Brother: Eita's brother Kouki left the dojo a year ago. He is the one that sends Aero Eita's way and starts the plot. It's implied that they aren't exactly close.
Artistic License - Biology: The harpies are clearly based more on what would be cool than what would actually work in real life. Especially obvious since the author's other work, Daily Life with Monster Girl, goes to a great deal of effort to make sure everyone's biology makes sense. Here, harpies have arms, wings coming out of their backs, and the women all have large breasts. Daily Life with Monster Girl harpies have arm-wings and apparently pubescent bodies to cut down on weight in order to be able to fly.
This is even extended to the entire tribe. Even the elders tend to have bad short-term memories.
Battle Boomerang: A very large one was used by War Leader Jawea. She claims that it can slice through metal.
Black Sheep: Aero had the misfortune of seeking sanctuary with the Harpy tribe just before the Gigas attacks started. War Leader Jawea blames it on her black wings. note Interestingly, in the full-colour cover of the first chapter (not the original one-shot) Aero is shown with blonde hair and dark blue wings, nowhere near black.
Dirty Old Man: Eita's grandfather and sensei. His ninja "dummy" would not look out of place in an H-game, and his interest in Eita's PSP is a visual novel—in which he is trying to achieve the "Harem" ending.
He gets very excited upon catching Aero's scent—the "scent of a woman."
Honor Before Reason: Lampshaded and Subverted. War Leader Jawea claims that the Harpy tribe will fend off the Gigas to protect their clan's honour. Eita advocates running away, to which War Leader Jawea (eventually) replies that doing so will leave over half of their tribe—the young, the elderly, and flightless— behind.
Power Fist: Eita has a magical gauntlet that gives him super-strength. It also allows him to borrow the powers of his lieutenants for particularly strong attacks, one of the few things that can destroy a Gigas. Appropriately, it is christened the Gigas Slayer.
Eita brought the original version of the gauntlet from Earth. With the help of his ninja training, it could deflect a projectile specifically made to destroy the metal it was made out of.
These are also the Golem girls' weapons of choice.
The Power of Friendship: Eita specifically fights for the sake of saving the Autana and his troops. It's implied that his army stays with and is loyal to him out of a sense of honour and personal debt more than anything else. Which is a very good thing, considering the army is almost always broke.
Schizo Tech: Justified and explained, as Autana (Cute Monster Girls/Boys) and Ausuna (Real World Humans) have been traveling between worlds for a while, so pieces of technology (i.e. a VHS) will get leaked into Live-Earth.
Magitek: Chapter 2 explains that, with the technology exchange that happens time to time, magical versions of real-world items were developed. Examples include the crystal ball television and alchemically-powered generators.
Chapter 4 reveals that smartphones have made it into Live-Earth, with working reception.
Harpy fashion is designed with mobility and flight in mind, keeping materials light and coverage at a minimum.
The Lizardmen are highly mobile, and thus wear only a few pieces of armour like steel shoulder pads, gauntlets, and boots.
Lamiae are half-snake, and shockingly fast for their size. If anything, armour is superfluous and clothing just a fashion statement.
Slimes can't really fit into most conventional clothes, being semi-liquid and naturally slippery.
Merfolk and Scylla spend the majority of their time underwater; anything larger and more flowing than a bikini will prove problematic when swimming, unless you specifically design it for hydrodynamics.
Kobolds, like Lamiae and Harpies, are a more feral breed of Autana, and use their speed and strength beside, requiring maximum mobility. What little items they don are to look more menacing.
Minotaurs are walking tanks. Armour is kept to a minimum, and they enjoy the freedom.
It would be problematic for Mummies to keep re-wrapping themselves, magically or not. When their bandages come undone, most just choose to keep it that way.
Trapped in Another World: While there is a way to get back to Earth, Aero mentioned that it would take a large amount of magical power to do so and a large amount of time to gather said power. In short, Eita's stuck until he finishes his quest.