Gantz

Legend has it that the human race is not the only dominant civilization living on Earth. Two other races exist in this world: the Makai (a demon race) and the Jujinkai (a half-man, half-beast race). Once every 3,000 years, a supreme being known as the Choujin (Overfiend) will emerge and bring balance to all three realms on Earth. In present-day Japan, after 300 years of endless searching, a Jujinkai named Amano Jyaku has discovered the presence of the Choujin inside high school slacker Tatsuo Nagumo. But now, Amano, along with his sister Megumi and their sidekick Kuroko, must protect Nagumo and his new girlfriend Akemi Ito from the Makai, who believe that Nagumo is not the Choujin, but an evil entity bent on destroying all living beings on Earth.

With the space program attempting to travel to Mars, 21st century scientists were tasked with warming up the planet so that humans could survive on its surface. They came up with an efficient and cost effective plan of sending cockroaches and mold to the surface so that the mold would absorb the sunlight and the insect corpses would serve as a food source for the mold. It is now the year 2577 and the first manned ship to Mars has landed on the planet and the six crew members are ready for their mission. But what they find are giant mutated humanoid cockroaches with incredible physical strength. The crew members are easily wiped out, but not before sending a transmission back to Earth. Now, humanity will send elite warriors to exterminate the mutated bugs and claim back Mars.

Now a member of Anteiku, Ken Kaneki grows closer to the ghouls around him. Determined to protect his new home against anti-ghoul forces, he trains his powers in secret. But when the infamous gourmet, Shū Tsukiyama, wishes to savour some half-ghoul flavour, Kaneki's training is put to test of a lifetime.

Hyakkimaru, a warrior on a quest to reclaim 48 of his body parts which were each taken by a demon, is joined by Dororo, a thief on a quest to avenge the death of her parents.

Tenshu is imprisoned and sentenced to death for murdering the men who raped his girlfriend. However, he manages to survive his execution and is presented with an option: face another execution attempt or subject himself to their bizarre and dangerous experiments.