Of Being an Overlord is the seventh episode of Disgaea: Hour of Darkness.
Laharl has just become the Overlord after reaching the Heart of Evil, and has since done nothing but laugh evilly, something which causes Flonne great concern. Etna decides to give Laharl his first task - but to his dismay, it is merely to round up the pets of a young and rather bratty demon named Aramis. Despite his protests, Laharl eventually acquieces to Etna's demands when she threatens to never acknowledge him as Overlord if he does not fulfil this task.
The group head to Salamander's Breath and discover that Aramis' pets are in fact zombies. They decide to simply beat the zombies up ("the usual method"), leading to Aramis and Etna discussing about how they rip up their own zombie pets. Etna reveals that as a child working in the the castle, she was teased and bullied by the other demon children. When her pet was killed by them, King Krichevskoy was the only one who offered her kindness. Because of this, Etna swore loyalty to the King, and vows to see that Laharl will grow up to be like him, hence her task.
In the Ember of Dreams, they meet the final group of Zombies. Laharl, grown sick of killing zombies, complains about how boring it is. Aramis, however, instructs them to be alert: one of the zombies is his masterpiece: a zombie constructed with the body of Hercules, brain of Mahogany and a Horse Wiener. Even Laharl is alarmed by the threat of the Horse Wiener, and immediately attacks the zombie.