Surrounded by a forest and a gated entrance, the Grace Field House is inhabited by orphans happily living together as one big family, looked after by their "Mama," Isabella. Although they are required to take tests daily, the children are free to spend their time as they see fit, usually playing outside, as long as they do not venture too far from the orphanage — a rule they are expected to follow no matter what. However, all good times must come to an end, as every few months, a child is adopted and sent to live with their new family... never to be heard from again.
However, the three oldest siblings have their suspicions about what is actually happening at the orphanage, and they are about to discover the cruel fate that awaits the children living at Grace Field, including the twisted nature of their beloved Mama.
In the not-too-distant future, two drifters traveling through the desert stumble across the biggest gold nugget ever found and the dream of immense wealth and greed takes hold. They hatch a plan to excavate their bounty, with one man leaving to secure the necessary tools while the other remains with the gold. The man who remains must endure harsh desert elements, ravenous wild dogs, and mysterious intruders, while battling the sinking suspicion that he has been abandoned to his fate.
Rick is a mentally-unbalanced but scientifically gifted old man who has recently reconnected with his family. He spends most of his time involving his young grandson Morty in dangerous, outlandish adventures throughout space and alternate universes. Compounded with Morty's already unstable family life, these events cause Morty much distress at home and school.
The story follows Issei Hyōdō, a dim-witted, lecherous second-year high school student who is killed by a girl on his first date ever. Issei is reincarnated as a devil, and from that day forward, he serves as an underling of Riasu, a high-level devil who is also the prettiest girl on Issei's campus.