Sidekick

Eric Needles: Eric is a boy who was adopted as the sidekick to Maxum Man, the greatest superhero of all time (before he disappeared).
Trevor Troublemeyer: Eric's best friend. Trevor always ropes Eric into all sorts of hijinks.
Kitty Ko: Kitty is a girl who, despite being a bit strange, gives the rest of the group advice, and is somewhat a good hacker and fixer.
Vana Glama: Vana is a hyper-ambitious prima donna who is not easily impressed and is extremely shallow.
Maxum Brain: Eric's guardian due to the fact that Maxum Man is missing.
Maxum Man: Eric's favorite superhero, before Eric became his current sidekick, with Superman-like powers.
Mr. Martin Troublemeyer/Master XOX: Trevor's father. All he wants is what is best for Trevor and for him to be a good boy, which is why Trevor can't stand him.
Professor Pamplemoose: The cruel Headmaster at the Sidekick Academy and Eric's grumpy teacher, Pampelmoose is a strict disciplinarian who runs the school like it was prison camp.
Golly Gee Kid: Golly Gee Kid was Maxum Man's sidekick in the old days, often seen in Maxum Man's Sidekick Academy training films.
Mandy Struction: A teenage student at the henchman school (though she would later become an anti-hero in later episodes) and Eric's new crush.