Mao's Dad is the Overlord of Evil Academy in Disgaea 3: Absence of Justice. Unlike some other Overlords, Mao's Dad is titanic in size. Despite his huge size and power, Mao's Dad isn't totally evil and actually just wants Evil Academy to be left alone and for the Demons of it to live carefree lives. Mao's Dad has a deadly signature attack, The Century Killer, which burns anything in its path to ash.
Before the game took place, Mao got angry at his dad for (once again) accidentally crushing his game system. Mao vowed revenge on his dad but the Overlord couldn't help but admire his son's determination. Later Super Hero Aurum comes to defeat Mao's Dad after hearing that he's the Strongest Overlord. Before the battle, Mao told Aurum his dad's weak points in response to his previous fight with his dad. Mao just wanted Aurum to teach the Overlord a lesson, but Aurum ended up killing Mao's Dad instead. The Overlord could have won by using the Century Killer but didn't because if he did, he would have harmed Mao. The Overlord's body and soul were then stuck to the Academy, unable to fully die. Mao believed that his father held a grudge against him and want to find a way to beat his father and let him rest in peace, thus setting up the game's events.
At the end of the game, Mao defeats Aurum in battle and then goes to see his dad. Proud of what Mao has become, the Overlord gives Mao the title of Overlord and moves onto the afterlife. Mao then promises to be an even stronger Overlord than his father.
However, in the Almaz ending, Mao's dad grants the title of overlord to Almaz (despite the fact that he's human).
- There is a joke ending for Laharl where he, along with his two Vassals Etna and Flonne, pretend to be Mao's Parents in order to become the main characters of Disgaea 3.