Fifteen years ago, disaster struck human civilization, and now dangerous man-eating monsters roam the ravaged lands, posing an existential threat to the remaining survivors. Amid this turmoil, an isolated facility shelters children and nurtures them in peace. However, as a few among them find out about the world beyond the narrow periphery of their nursery's walls, their curiosity about it slowly grows. Meanwhile, in the outside world, young survivors Maru and Kiruko band together to search for a special place called Heaven, each for their own reasons. Carrying past burdens and tragic secrets, the two hope to find answers to the cruelty they have experienced in their lives and in the world, which still remains in tatters.

Upon witnessing a man's head cracked open with an axe, 16-year-old Yuri Honjou trembles in fear and confusion as she flees from the masked assailant, only to find out she's trapped in an abandoned building where every door is mysteriously locked. Desperately searching for a way out, Yuri runs to the rooftop, but a world with no signs of life stands before her, surrounded by high-rise buildings. Though filled with despair, once she learns that her brother is also in this strange place, Yuri is determined to find him and escape. However, she soon finds that there are more masked murderers in the area, anxious to terrorize their newfound victims and satiate their sickest desires, leaving Yuri to question if they will be able to make it out alive.

A young girl named Miru and Ran, a boy who appeared before Miru, embark on an adventure in an alternate world — but something tragic awaits them there... (Source: ANN)

Seventeen-year-old Tenchi Masaki grew up hearing stories about how his ancestor used a sword to seal a demon inside a cave seven hundred years ago. When curiosity gets the better of him, Tenchi goes to the cave and stumbles across the sword from the legend. Thinking that the story is nothing more than a fairy tale, he removes the blade and inadvertently releases the demon, who turns out to be a space pirate named Ryouko Hakubi. Furious about being trapped for so long, she attacks Tenchi, but he is able to repel her with the sword, awakening his inner power. After seeing this, Ryouko takes an interest in her unlikely savior and decides to crash at his place. As if it were a chain reaction, more alien women—Aeka Jurai Masaki, an uptight princess from the planet Jurai; Sasami, Aeka's sweet younger sister; Mihoshi Kuramitsu, a ditzy Galactic Police Officer; and Washuu Hakubi, a wisecracking genius—gradually come in contact with Tenchi and begin living with him. Through his encounters with these five women, Tenchi begins to learn more about his ancestry, newfound power, and the looming threat lurking beyond the skies.