Capable of making bio-mechanical weapons out of human flesh, alien parasites grotesquely invade the Earth, turning their hosts into maniacal killers who seek and destroy each other to the bloody death! And yes, it s also a human love story, even though the budding romantics are infested with slimy, tumor-like globules.

Momotaro and Hidemaro are 1st-years at Otokojuku, a private boys school where true men are made. Momotaro, proficient in academics and martial arts becomes good friends with Hidemaro an underachieving weakling. Omito Date, former student leader, plans his revenge against his former school. Now leader of an evil army from rival Kanto Gogakuren school he fully intends on taking over Otokojuku.

Momotaro and Hidemaro are 1st-years at Otokojuku, a private boys school where true men are made. Momotaro, proficient in academics and martial arts becomes good friends with Hidemaro an underachieving weakling. Omito Date, former student leader, plans his revenge against his former school. Now leader of an evil army from rival Kanto Gogakuren school he fully intends on taking over Otokojuku.

After four years overseas, Shozo returns to Japan to avenge his yakuza boss who was assassinated by his own treacherous top man, Kurawaki. The resulting battle leaves both men severely injured, and Shozo awakens in a mysterious medical facility to find his arm replaced with an M61 Vulcan cannon and his leg replaced with a rocket launcher. Meanwhile, Kurawaki has been fitted with mechanical augmentations of his own. Get ready for the second round.

After four years overseas, Shozo returns to Japan to avenge his yakuza boss who was assassinated by his own treacherous top man, Kurawaki. The resulting battle leaves both men severely injured, and Shozo awakens in a mysterious medical facility to find his arm replaced with an M61 Vulcan cannon and his leg replaced with a rocket launcher. Meanwhile, Kurawaki has been fitted with mechanical augmentations of his own. Get ready for the second round.

The Amamiya Brothers, Masaki and Hiroto, keep looking for their older brother Takeru who disappeared one year ago. The three Amamiya brothers lost their parents when they were young. Since then, they relied only on each other. On the anniversary of their parents' death, Masaki and Hiroto expect Takeru to appear. Instead, they meet a person who has a clue on Takeru's whereabouts.

Rin a young high school student is your everyday awkward girl who gets bullied by her fellow students. On her 16th birthday, Rin gets an unexpected surprise: she finds out that she is, on her father's side, a half-mutant.

At Aitoku High School, repeat sophomores Kōji Katō and Tōru Nakama are bruiser fighters who scorn any flashy titles. They pursue honor student Kyōko Izumi alongside their loyal crew. When rival gang leader Teru’s “bontan-gari” attacks sweep through the district, even Aitoku’s toughest, including Kintarō and Junpei, fall prey, until Kōji and Tōru themselves are targeted and Kyōko is kidnapped by Teru…

A former special forces operative struggling to contain the destructive impulses of his past goes on a rampage against a squad of ruthless assassins.