The Demon Lord who presides over "Sloth" of the Seven Deadly Sins. A lazy slacker who hates effort. He usually spends his time sleeping. Belphegor was bored. Video games were dull, and TV was boring. He had too much time on his hands. Then he thought, "I'm bored... I know, I'll conquer the world." He decided to conquer the world on a whim. He immediately launched his flying Demon Lord Castle and released monsters into the world. However, those monsters are just as lazy and unmotivated as their master. Some are even in a sightseeing mood. The Demon Lord appears before you and carries you off to his castle. It's a total cliché. He welcomes you and prepares various comforts. As always, he's looking forward to the Hero's party arriving.

Your childhood friend. You've known each other forever. Kazuma was laid off from his job and was wandering the streets when he happened to see an ad for "Hero Wanted" and applied. It was meant to be a joke, but he actually got hired, so he's working as a Hero out of necessity. You were kidnapped by Demon Lord Belphegor, but he figured it was just the usual routine and is reluctantly heading to the Demon Lord Castle.

Hero Kazuma's best friend and colleague. Because his name is written as Hideo (Hero), people treat him like a legendary Champion. He is actually just an ordinary guy. No matter how much he says, "I'm not a Champion! I'm Hideo!" no one listens, and they keep bringing him requests. He has incredible luck and somehow manages to pull through in the end.

A serious swordsman who came to slay Demon Lord Belphegor. He is calm, cool, and collected. Very earnest. Because of this, he is inflexible and doesn't understand jokes. He believes Belphegor is a Great Demon Lord who will destroy the world. Even if you tell him Belphegor isn't a bad guy, he won't believe it. He plays the straight man, but he's also airheaded. Sometimes he gets swept up in the chaos and becomes the one acting silly. When that happens, you'll have to be the one to call him out.

A former human. While he was working as a lackey for his seniors, he was attacked by a vampire and turned into one himself. However, even as a vampire, his status as a lackey hasn't changed; now he's Demon Lord Belphegor's errand boy. He will be your personal servant. Please give him any order you like. Perhaps out of old habit, he praises others to avoid making them angry. Lately, he's just a pathetic guy being bossed around unreasonably by other vampires.

Saucer Grand is a vampire whose personality changes with the phases of the moon. Usually quiet, he becomes hyperactive during a full moon. He is the one who turned Itchi into a vampire. Itchi was unlucky enough to run into him during a full moon. Outside of the full moon, he is relatively calm. He has taken a liking to you and wants to suck your blood. He asks to suck your blood whenever he gets a chance. "Just a sip. Seriously, just one sip." Can he be trusted?