【PC】銃刀｜GUN-KATANA ―Non-Human-Killer―

人間の住む社会において、人間とその姿形は全く変わらず真の姿を隠して紛れ込んでいる存在＝Non-Human、通称人間もどき。どこから来たのか、何の目的で人間社会に潜んでいるのかは不明。人間の皮をかぶり、突如牙をむく人類共通の敵。この敵に対抗する組織Gate of Ishter（ゲイト・オブ・イシター）、通称GoIの設立によって、人間とNon-Humanとの戦いは苛烈を極めてゆく・・・。

優しい家族と幸せに暮らす、どこにでもいそうな中学生の時原姫菜と弟の雹は、とある事件をきっかけにGoIの特殊施設Hate Breed（ヘイトブリード）に投獄される。そこは、それまでの生活と打って変わって地獄の日々を告げる場所であり、生きるために相手を殺すことを宿命づけられた場所でもあるのだ。

過酷を極めた地獄のような牢獄生活を脱した姫菜を待っていたのはGoIの奴隷としてNon-Humanを殺し続けなければならないFR Slayer(フリーランク・スレイヤー）という身分だった。姫菜と雹は自分達自身の真の自由を勝ち取るため、そして何より自分達自身が生き残るために戦いに身を投じることとなる・・・。

Non-Humanの殺戮を繰り返す日々、いつしかそれが当たり前のようになってきた姫菜と雹。GoIエージェントの陶山が持ってきた次の仕事は無人島である瑠門島での大規模作戦に参加し、一体でも多くのNon-Humanを殲滅することだった・・・。

Humans, and the mysterious enemy who resembles them--collectively termed "Non-Humans".

In the midst of this racial dispute, this is a story of various people who pursue their own objectives--writhing in agony, opposing fate.

A heavy collar fixed to her neck, a robotic shackle that counts down to her freedom.

Himena, released from countless days of prison to be reborn as a murderer.

These were the words that were burned into her consciousness at the prison "Hate Breed":

"These are the Non-Humans. Your enemy, the enemy of humanity. Kill, kill, and kill some more. That's your sole path to freedom."

Slaves allowed to live only as long as they continue killing: the FR Slayers.

A robotic counter on the collar increased with each enemy terminated.

To survive, their only choice was to put their lives on the line, again and again.

In the midst of this, a new mission was given to FR Slayer Himena.

Long neglected, a no man's land that no one dared approach: the abandoned island Rumon. There hid an influential Non-Human.

To score kills and raise her counter, Himena enthusiastically set out to Rumon Island. Yet this turned out to be a strategically vital region, so important that the elite squad "Saints" had been dispatched.

Just who are the Non-Humans? And which side will prevail in the end?

Humans and those who defy them--a survival game staking the fate of their species begins.

[From a post on the MangaGamer forums]