Gid Lucione Deviluke

The King of Deviluke and Emperor of the Milky Way Galaxy, Gid is the father of Lala, Nana, and Momo.

With him being the head of the Devilukean family, his second name (Lucion) might be a reference to Lucifer. This pattern can be seen in his daughters' names too.

Appearance
Despite his near omnipotent power, he has the physical appearance of a child, looking slightly devilish, with shark-like teeth, spiky black hair, and the characteristic Devilukean tail. While his daughters' tails end in spades, his appears as a wicked looking trident. Originaly he was lot taller, but Lala states that due to overusing his powers during the "Galaxy Unification Wars", he apparently shrunk down to the size of a child. However even in this form he is described to still be very powerful, stating he could destroy the Earth if he released it.

Personality
Gid appears to be very spoiled, bratty and perverted, going as far as to use his child-like appearance to get close to pretty girls. Lala claims the only reason he wants her to get married is so he can step down as king and be free to pursue his perverted hobbies. He threatened Rito that he could easily destroy Earth, and would do it if Rito did not satisfy him as his heir.

In the manga, he seems more easygoing and is much more accepting of Rito as his heir, where he simply wishes to relinquish the throne so he could pursue his perverted interests. However, in the anime, he is much more critical of Rito and even attacks him, saying that Rito is not suitable for Lala.

Daughters
Gid is the father of Lala, Nana, and Momo, whom he can be quite demanding towards when they disobey his orders like running away from home. While his daughters love each other like family, there is little evidence that they also love him as a father, and equally little evidence that Gid really cares for his daughters. In their earlier childhood on Deviluke, Lala and her sisters appear to usually be left alone in their palace by their parents to play around, pull pranks, or study until they get bored.

Because Gid is quite bratty and spoiled, most of his choices regarding his daughters are usually for his own benefit rather than out of love for them. For example, he pushes Lala towards marriage until she decides to flee to Earth. In the manga, when Lala chose Rito as her groom, Gid gleefully pushed them towards their marriage, even already deciding on a wedding date, and threatened to destroy Earth if Rito does not agree. Lala knew that rather than truly respecting his daughter's choice, he's really only pushing their marriage so that he may step down as king and finally be free to fool around.

Unknown Wife
Gid has a wife, who has yet to make an appearance. It is unknown exactly how her relationship with him is, especially considering his intention to step down from the throne to go around doing perverted things to other women.

She is described to be hardworking, more reliable and better at politics than Gid is, and their daughters seem love and admire her a lot more than their father.

Zastin Deviluke
Zastin is practically Gid's most loyal subject, and he respects him the most as the King of the planet Deviluke and Emperor of the entire Milky Way Galaxy. He is one of the bodyguards who protect the king's family members   and would get mad at anyone if they disrespect any of them.

Due to having the same last name, it's possible that he is related to him in a way, but this is unconfirmed and unlikely.

Rito Yuuki
When Rito became engaged to Lala, Gid demanded that he would have to meet Gid's expectations to take care of her, otherwise he would destroy the Earth. He doesn't seem care for him that much, like when he forced him to marry Lala for his own benefit to step down from the throne and fool around with other girls. However he does seem to trust him enough to take care of his daughters, as they all live within his house.

Rito and Gid have met only once, but after Lala used her invention, Bye-Bye Memory-Kun, to erase memories of herself from the memories of the people on Earth, it's difficult to determine how they now regard each other, even though the invention mostly failed.

In the manga, he doesn't take his role as king seriously, and wishes to dump the job on Rito soon. But in the anime, he is much more critical and antagonistic toward Rito and challenges him to prove himself.