If you were to find one underlying theme across almost all of Kamachi Kazuma's works - it would be systems. For each universe he creates a system, and we then follow a series of characters adventures both working within and against said systems.

For Heavy Object, the system is the concept of a 'clean war' - which is enforced by the use of 'Objects', giant 50m+ spherical, 200,000 ton+ machines of war, which are covered in over 100 different cannons, lasers and railguns, and can survive a direct impact from a nuclear explosion (they are basically slightly more realistic versions of the giant mechanised weapon, i.e Gundam) . Humanity has moved from the Nuclear Age of war, to relying on these giant monstrosities as proxies for battle. An Object can only be defeated by another Object - and this adage is what allows the four world powers to engage in wars without sacrificing 'flesh-and-blood' lives.

However, our heroes Qwenthur and Havia make one rather profound error in this age of the 'clean war' - they defeat an Object as 'flesh-and-blood' soldiers. This leads our pair, and the various other characters of the 37th CMB, across the world in a series of events that would almost make you pity our heroic pair, if they weren't complete idiots.

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At its heart, Heavy Object is a comedic David vs. Goliath action adventure with a pair of rather unconventional heroes who are inclined to complain about almost any order they are given, make a pass on any female they come across, and somehow manage to ruin any accomplishment they perform. It is designed to be somewhat modular - in which after the first volume you can read almost any other volume out of order. Some would argue that this leads to the series suffering a reduction in individual character development. However I like to disagree. The format of this series doesn't require a lot of individual character development, it's almost an 'Object of the week' format which is more about the antics of our heroes along the journey rather than an overarching plot.

I would still recommend that the series be read in volume order however. Character development is actually present, although it's more like receiving small patches for each character as each volume progresses. It's not explicit, but it's still there - and there are some things you may learn in an earlier volume that are not mentioned at all in a later volume, but can provide some added context to a later situation.

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Qwenther is the brains of our two-man operation. He's in love with Objects - and perhaps he enjoys them too much. He'll pant at any opportunity to get close to an Object and its secrets, even if it belongs to the enemy. He's also not an actual soldier - he's a 'battlefield student'. This means that he doesn't actually get to carry any weapons, other than a seemingly infinite supply of plastic explosives.

Havia is the muscle of our two-man team - but that doesn't mean he's an idiot. He's incredibly intelligent radar-analyst who never actually gets to analyze radars, and has undergone the military training to survive any battlefield. He's the opposite of Qwenther when it comes to Objects, he's ready to make a run for it the moment one is mentioned although circumstances unfortunately never allow him to.

Milinda is the 'princess' of the 37th, and is the Elite Pilot of their attached Object, the Baby Magnum. She's incredibly competitive when it comes to Objects, seeing as hers is a near obsolete First Generation, and quite possessive of Qwenther, which only he hasn't realized yet. She is actually an incredibly skilled Elite, and can often hold her own against most Second Generation Objects she comes across, until our duo can set her up with the perfect shot (whilst our duo hopes that she doesn't kill them by accident).

Frolaytia is the commander of the 37th CMB. An opportunity to make a pass on stylish figure seems to account for 30% of our duo's motivation to actually get anything done. She's a Japanophile whose relatively cruel demeanor hides her soft attitude towards her subordinates. Her attempts to prevent our ever unfortunate problem duo from entering any trouble with simple tasks often ends up in them causing even more chaos, and this loop is the basis of many of the series events.

Besides our four main cast and the numerous individuals within the 37th, each volume tends to have one or two additional characters who receive a fair portion of the spotlight. They vary from allies to enemies, and many of them often will reappear in subsequent events to varying degrees. Once you hit the later volumes, the web of characters and their relationships among the world powers is so large that it's almost a guarantee that someone you recognize will have a role to play in later events.

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As stated earlier - each volume is relatively self contained and follows a consistent format of three parts. Part One often builds the framework for the system Kamachi Kazuma has created for the volume, how it either works within or against the system of Objects and 'clean wars' that underpins the series, and often resolves a local event. Part Two continues to build the framework and the pieces of the system, and involves an event either directly or indirectly related to the event in Part One. Part Three is where the system is completed, and our heroes must find a way to dismantle or work within the system to solve the final crises. Each part tends to involve a battle with or against an Object in some form.

Regarding art, there isn't much to discuss. Quality of illustrations is on the level you would expect from any Light Novel commercially produced today. Each volume often has a couple illustrations of our duo, and any other prominent characters involved. Additionally, each Object that appears gets a specification sheet with a general outline of its form. I would prefer a direct representation of the Object (some volumes have one as a background for the contents and cover page), however the in text descriptions are enough for you to form a mental image with the schematics.

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All in all, Heavy Object is just a bit of fun. Whilst it isn't categorized as a comedy, the comedic attitudes and antics of our heroic pair are what make this series. It has its sci-fi, mecha, and military, and action elements of course, and these facets are the basis of the series. However, if you come in expecting something serious or overly heartfelt, this is the wrong place. This is all about watching two idiots combat giant 50m+ spherical, 200,000 ton+ machines of war with only some plastic explosives, a rifle and a rocket launcher, and ingenuity, whilst listening to them complain about it the whole time.