An isolated island is discovered, and its seemingly time-forgotten inhabitants are now being reintroduced into society. However, the truth is that the island was the hidden home of many supernatural creatures, and that it was actually the Onigashima of the legendary demon-fighting, peach-born Momotaro's adventure. Some of these demons seek to take their vengeance on the descendants of Momotaro. The Momotaro descendant, Momomoto Akira, is a middle school girl who reluctantly becomes a friend of one of the transfer students, and then soon becomes a target of the other vengeance-seeking demons!

(Source: MangaHelpers)

Humanity is on the brink of extinction as a flower known as “Viscar” infects humans and animals, turning them into mindless hosts that feed on others. If you get bitten by the infected, or inhale the pollen that emits from their bodies, the flower will plant itself into your brain. Humanity is fighting a losing battle against this world-wide pandemic, and most people have given up hope.

Volt was once part of the army and had been assigned to be the guard of Dr. Kisling, the scientist leading the development of a vaccine to fight against the Viscar. From an unfortunate accident, one of the contained Viscar pollen escaped, infecting Dr. Kisling. Dr. Kisling’s final wish to Volt was to find his daughter Lilith, and, with her help, continue the development of the vaccine. Lilith and Volt now venture into the post-apocalyptic world to bring back hope to humanity. [DrCoke]. — quoted from Mangahelper