Gaius

In Battlestar Galactica, Gaius Baltar was used by a Cylon spy to help bring about the holocaust that killed most of humanity. He was rescued from Caprica, and ended up on Galactica. He invented a Cylon detector, and led a monotheistic cult. He was also elected President of the twelve colonies.

In Frank Herbert's Dune, Gaius Helen Mohaim was a Bene Gesserit Reverend Mother. She was part of the conspiracy to end Paul Atreides' rule, and was later executed by Alia Antreides.

In Jim Butcher's Codex Alera series, House Gaius is a ruling house of Alera.

In Final Fantasy XIV: A Realm Reborn, Gaius van Baelsar was a general who lead the invasion into Eorzea. He was known as The Black Wolf.

Gaius is a Latin name from ancient Rome, and means 'Happy'. Only 15 boys in the United States were named Gaius in 2015.

Aeon

Aeon Flux began as an animated short on Mtv in the 1990s. By the third and final season, it grew from a few minutes in length to a full half hour. In 2005, it became a live action film starring Charlize Theron, which spawned a video game and a comic book. Aeon was a secret agent from the nation of Monica, who infiltrated the neighboring police state Bregna, which was led by her nemesis and lover, Trevor Goodchild.

Aeons were a type of creature in the Final Fantasy series of role playing video games. They were powerful creatures that could be summoned and controlled by the player. They were a physical manifestation of the dreams of the Fayth, people whose souls were removed from their still living bodies and sealed into stone tablets. 

Aeon was a Latin transliteration of a Greek word that meant life or lifespan but has evolved into the English word Eon, meaning age, or a long period of time. In 2011, the name Aeon was given to 7 girls.