Truly a terrible series, but boy does it have a wonderful idea. The concept is excellent. Cockroaches used to establish Mars as a place for humans to move to in order to deal with overpopulation, but things go wrong and the roaches somehow evolve into hostile sentient creatures. In this way it boils down to a war between humans and cockroaches, but now the roaches are the dominant being.

It sounds so great on paper, but the execution is among the absolute worst I have ever encountered in a manga. In the end of the day it is your typical battle shounen, except quite a deal worse than even that. It is a poor man's Gantz. A poor man's last portion of Gantz in fact; that's just how bad it is.

Where things really get shaky is the setting. Despite taking place in 2600, the environment, the "politics", the dialogue, and the characters are all straight out of a dated and stereotypical 1940s racist depiction of the world. There is no logic behind anything that happens. It really boils down to just random fun facts the author acquires probably on his spare time and then he throws it into the series however he can see fit. Despite taking place well into the future, there really is nothing futuristic about it. It's as though the author wanted to write a science fiction without putting in the effort. Instead we get highly stereotypical depictions of characters based on their race at a point in time where such things would hardly matter.

All it boils down to is Japanese supremacy in everything. The Japanese characters are the masters, Japan is the most important country, etc... It's fine to do something like this, but when the writing is so nonsensically bad and so ill-fit for the occasion, it becomes straight up unforgivable. I have very high tolerance, but within ten chapters I straight up hated the manga and I tried giving it another seventy more chapters before killing over in defeat. I cannot recommend this to anyone on the planet, no matter what period in time or what country they come from. I think even a small child is too intelligent to enjoy this. Just stick to Attack on Titan, Gantz, or both.