S01E01 Meros Warrior
Bocca Serenade, is unhappy with his high school life. And wants to become a warrior like the ones from the story told to him by Tsunagi.
Bocca finally learns that the robot creature he fought before was from the organization, Monster Union, who are humans who serve under the monsters, using the robot creatures as their weapons.Keiko Hamasaki, the sister of Kew, and the owner of the inn, remembers her past, and is reminded of why she joined the Monster Union. Later, the robot creature strikes again, and Bocca is faced with it again, giving Bocca a great surprise.
After a war occurred in the 20th century between humans and demons. Since that time, the monsters rule the world in fear but keep relatively hidden from public view. A boy named Bokka ponders the past and wonders what became of the Meros Warriors who defended the world so bravely against the demons.