Residents of the Overlord's Castle
Zommie - Hangs out near the dimensional gateway, in the shops area of the castle. Zommie is a zombie who's never had a bath in his life. He tends to act as the main voice for the other vassals, suggesting he might be somewhat their leader.
Dratti - Usually found in the throne room. A powerful dragon who is actually a female. She tends to use a lot of ♥s and ♫'s at the end of her sentences.
Manty - A chimera and one of the strongest vassals in the Overlord's Castle, but he usually doesn't do anything, so it doesn't count for much. Also usually seen in the throne room.
Goleck - A golem who's also commonly found hanging around the throne room. He's very proud he doesn't wash his hands after using the restroom. He likes building plastic models, especially warships.
Ghoss - A ghost who tends to like handing out advice. He doesn't like his job and he never does anything to stop intruders. (Not that the others do either.) Usually found in the castle hallways.
Gargo - A gargoyle, Gargo is the father of two children, so he looks after Laharl, too. He'll scold Laharl if he gets too dependent, though. Also found usually milling around the hallways.
Longinus - A fine spear that Krichevskoy once used. Since Krichevskoy's death, he has been waiting for a new master to appear. He is found in a corner outside the throne room, where he offers information about weapons.
Aramis - Etna's follower who keeps zombies as pets. He is conceited, but obedient to Etna. He's a genius at making zombies, having particular interest in creating the ultimate zombie. While rude to Laharl originally, he's now much more respectful towards him. When he's older, Laharl intends to make him a vassal.
Pameel - A magic knight who is always standing in the same spot, but she never helps out. She sometimes joins the Dark Assembly and opposes your propositions. Who knows what she's really after?
Pleinair - Guide to the Dark Assembly. She'll teach you all about the assembly and how it affects daily life in the Netherworld. She'll also show you the way to the assembly.
Shell - A female samurai who's the receptionist at the Netherworld Hospital. Shell can treat all your injuries at once.
Polly - A red mage who's an expert on the Item World. She manages the item residents and guides you to the Item World.
Fiona - Keeper of the Dimension Gate, which sees more use than the castle's front door. This healer normally makes sure you don't get lost to wherever you're trying to go, but right now she can't send you anywhere.
Ecoille - The friendly archer who is one of two shop keepers of the Rosen Queen Co. Netherworld Branch. She specializes in the sale of weapons.
Gaston - The other shop keeper of the Rozen Queen, Gaston sells armour and healing items.
Penguin-like creatures that are actually containers for sinful human souls. Prinnies are trained to always say dood at the end of their sentences, though there are a few exceptions. They also explode when thrown, so do be careful. In the castle, they largely serve Etna, but Etna's vassals are Laharl's vassals, so they are largely obedient to him, too.
Information from the World Book:
Fact 1: Prinnies have human souls!?
Prinnies exist in both Celestia and the Netherworld, and they are inhabited by the souls of humans who have committed grievous sins. The Prinnies in heaven work for free, helping with menial tasks such as cleaning, cooking and doing the laundry in order to atone for their crimes. The Prinnies in the Netherworld, however, are paid less than minimum wage to fight as soldiers and act as lookouts until they save enough to buy redemption. The Prinnies of the Overlord's Castle work 20 back-breaking hours a day with no rest, but they booze it up and slack off when Laharl is asleep. Since Prinnies are just containers for spirits, they all look much alike, but sometimes the spirit inside will affect their color or expression.
-The Prinnies in the Netherworld are stingy and will do anything for money.-
-Only Death can remove a spirit from the Prinny.-
Fact 2: Prinnies Reincarnate by the Power of the Red Moon
The souls of Prinnies who have atoned for their sins are removed by Death and sent to the Red Moon, where their spirit is purified and reincarnated. Angels and demons both pay for their crimes by becoming Prinnies, so the system holds power over both the Netherworld and Celestia. Death is like a shepherd, guiding the Prinnies to the Red Moon. Maybe Death is a wandering spirit like the Prinnies.
-When the Red Moon is full, you can watch the Prinny spirits ascend.-
-It is the Grim Reaper's job to take Prinnies to the Red Moon.-
Fact 3: The Land of Rebel Prinnies
The Prinnies work hard to make up for their crimes, but some of them get fed up and flee the Netherworld to hide out in Prinny Land.
In Celestia and the Netherworld all Prinnies are equal, but in Prinny land there is a strict hierarchy. The stronger Prinnies keep order in this lawless land. Some of the toughest Prinnies were exiled here when they rebelled against the Overlord or the Seraph. Watch out for them.
-It is a weird land full of Prinnies. They like to fight, so be careful.-