Sometime in the future in a world not exactly unlike Earth, a nation named Edenia has taken over all but a small portion of the land under the command of Supreme Leader David Atlas. The majority on the world runs on electricity produced from Thundercore, which has allowed a variety of technological advancements, including the advent of airships. However, Thundercore energy holds a dark secret; the best place to harvest it from is from literal human resources. A series of children, altered from birth and capable of generating massive amounts of Thundercore, are kept in an orphanage run by Professor Durant away from the eye of Edenia. After an attack which results in most of the children kidnapped and Durant dead, the sole survivor, Tatsu Frampt, takes matters into his own hands to overthrow the corrupt system and free the Thundercore people.
Running for fourteen chapters over a course of three months, Red Sprite went the way of Yagi's previous work Iron Knight and was unfortunately cancelled in November of 2016. All chapters have been scanlated.
This manga provides examples of:
- Big Bad: Supreme Leader David Atlas, the ruler of Edenia and the one behind the Thundercore system.
- Can't Hold His Liquor: One sip is all it takes to floor Tatsu. Granted, he's a kid.
- Cool Airship: A bunch of them, all powered through Thundercore energy. Tatsu's own airship, the titular Red Sprite, Bristol's Excalibur, and the Atlas come to mind.
- Family-Unfriendly Death: Though this runs in a shonen magazine, more than a few are present. The worst are probably Durant having his heart crushed by Shepherd, Shepherd herself suffering that exact same fate later, and Atlas electrocuting one of his own men into a smoking skeleton.
- Karma Houdini: Atlas, although this is more fault of cancellation rather than deliberate evasion of justice.
- Kid Hero: Tatsu Frampt. He's only a child in the first chapter and isn't much older than a teenager after six years pass.
- Powered by a Forsaken Child: The dark secret of Thundercore energy; since only so much Thundercore can be taken from natural resources like fossils, most of it is cultivated directly from people who create Thundercore, ultimately leaving them as dried husks.
- Shrinking Violet: Mono was this during his time at the orphanage. Granted, although he's still quiet and soft-spoken six years later, he seems to have mostly grown out of this when Tatsu saves him.
- Super Soldier: The Crusaders, members of Edenia's army and Thundercore people who are said to be at least as powerful as Tatsu and Mono.
- Time Skip: Six years pass between the beginning and the end of the first chapter, during which Tatsu trains himself to be capable of attacking Edenia's soldiers with his command over the Thundercore energy running within him.
- Would Hurt a Child: Shepherd is only too happy to bomb an orphanage and use the children Durant is keeping as living generators until they are reduced to literal husks. Same with Bristol, who gleefully tortures Tatsu with an electric rod while gloating the power he's using to torture Tatsu with comes from a massive amount of Thundercore people harvested.
- You Are What You Hate: Atlas is implied to be a Thundercore human himself despite his usage of them as cattle, if his ability to electrocute a subordinate of his to ash through touch alone is anything to judge.