Year 2124, Christopher is on research expedition on Mars but he discover a missing commercial vessel...

When Hiro Hiyorimi tries to save a beautiful young woman from certain death, he ends up a dead hero himself! However, since the drop-dead girl is Hime, daughter of the King of the Monsters, his "reward" is to come back as a not-quite-living soldier in her honor guard of horror! That means helping fight off the army of supernatural monstrosities Hime's siblings are unleashing against her in hopes of moving up the ladder of succession. And if facing off with vampires and zombies isn't bad enough, how can anyone be prepared for the REALLY weird ones, like were-sharks, pandas and killer dumplings? This sure as hell isn't the afterlife Hiro was hoping for, but the really sad part is that Hime is the good girl in all of this... or at least as close to good as you can come when you're on the wrong side of the gates of hell!

Recap of the first season of Hitori no Shita: The Outcast that aired a week prior to Japanese broadcast of the second season.

Dreaming of a magical world every night, the young Toramizu Ginta yearns to be able to go there. With only his friend Koyuki believing in his dreams, Ginta remains positive despite the slander he receives from others over his dreams. But his wishes are answered, as one day a large door appears in front of Ginta, summoning him to the land of MAR Heaven. In this land, the weapons known as ARMS exist. While initially Ginta greatly enjoyed the discovery of this magical world, he soon learns of the terrible wars that have once plagued MAR Heaven and the upcoming war that may soon appear.