Lordgenome is the ominous Spiral King, who rules the planet from his capitol city, Teppelin. An immortal human who lived for more than 1000 years so far, he cares little for people, treating the strange girls he surrounds himself with as dolls to be cast aside when they've outlived their interest to him. From Guame we find out that Lordgenome despises human consciousness and self-awareness although we are yet to be given a reason for this dislike.
[Spoiler] When Simon and Nia finally reach him, he claims that the act of trapping the humans underground and hunting down those who live on the surface is a means he has found to protect mankind, because according to him, when the population of humans on the surface reach one million, a terrible fate will fall upon them. He also shares the fact that he and Simon share the same "Spiral" powers, before being defeated via being stabbed in the chest by Simon's Core Drill. [/Spoiler]
[Spoiler] In episode 18, Lordgenome's memories are retrieved by Rossiu's research team, and he reveals to Rossiu the truth about the Anti-Spirals, and the reason why he forced mankind to live underground in order to control its population. It is also revealed that at one time Lordgenome had even been part of a group that fought against the Anti-Spirals, the Spiral Knights, who fought and protected the galaxy from the Anti-Spiral menace. In the end, however, the Spiral Tribe lost the war, and the Anti-Spiral Tribe (The Han-Rasen Tribe) gained control of the universe. [/Spoiler]
[Spoiler] Lordgenome's revived head was used to control the massive spaceship Arc-Gurren. According to Leeron, the ship only reacts to him just like the Lagann only works with Simon. After the Gurren Brigade gained control of the Cathedral Terra, it was relocated there, apparently for the same reason. [/Spoiler]
(Source: Wikipedia)
