Living in the slums of a wealthy town, Rudo and his foster father Regto try to coexist with the rest of the town's residents, but Rudo despises the wastefulness of the upper class. Ignoring the warnings from those around him, Rudo regularly rummages through the town's garbage in search of anything useful or valuable to save from the "Abyss"—a massive hole where anything considered trash is dumped, including people. Rudo's biological father was one such person, having been thrown into the Abyss after he was accused of murder. One day, after running into a mysterious figure on the way home, Rudo returns to find Regto's dying body on the floor. He is immediately found at the scene by the authorities and is charged with murder. No one believes his claims of innocence, and he is thrown into the Abyss. Instead of dying, however, he finds himself in a strange, foul-smelling place surrounded by monsters made out of trash. When Rudo is attacked by said monsters, he is saved by a man named Enjin, who reveals himself to be a "Cleaner"—someone who uses special weapons called Vital Instruments to combat these creatures. In order to get his revenge on the one who killed Regto, Rudo reluctantly becomes a Cleaner to fight his way back up and out of the Abyss.

Renji Kusakabe, an arcade employee, one day notices a small foreign girl struggling to win a stuffed toy called "Manly Koala" from a crane game. Three hours later, after finishing his shift, Renji sees the girl still at the game, but the toy remains unmoved. Feeling sorry for her, he decides to help. He inserts a 100-yen coin and, with one skillful try, wins the toy, which he then hands to the girl. Startled by this unexpected gesture, the girl looks at Renji with suspicion. Flustered, Renji hastily tells her it's a Valentine's Day gift. Little does he know, in her home country of England, Valentine's Day is traditionally when men give women gifts along with a confession of love.

Third season of .

Wrongly convicted of a crime, 34-year-old Shigeru Yoshioka loses everything, including his trust in women, and withdraws from society as an unemployed recluse. One day, he stumbles upon a way to travel to another world. When a mysterious status screen appears on his computer, Shigeru sacrifices his looks to gain an overwhelming 100 trillion and 5,100 parameters. Now reborn as an "Absolute God," he begins his second life in another world.