Luis

Luis is arguably the smartest in the crew and prefers to stay in the ship to avoid the future's hostile environments and dangerous creatures. He often freaks out and is slightly obsessive over hygiene and germs. His full name is Luis Calabasas.

His genius-level intelligence and technical aptitude has allowed him to figure out the advanced technology within the Time Flyer — even surpassing the capabilities of C.G. — and more then once, this has helped him help save the day. At one point, he wrote a basic but temporary operating system from scratch, when the ship's system crashed in an ion storm.

Appearance
He is tall and lanky. He has black hair and brown eyes. He is dressed in a black, long-sleeve shirt, with a dark-gray t-shirt with skull design, and bluejeans.

Personality
Luis is highly intelligent with an interest in nerdy pursuits, like science, sci-fi, and electronics. Where the other kids enjoy exploring new environments, he is afraid of most things in nature (germs, animals, bad weather, etc.), so he would rather read up on it from the peace and safety of ship's computer. Of the crew, he is the quintessential "brains" of the team. He is also the whiner of the team, because of his habit of whining and complaining, which causes Ethan to call him the "King of all Whiners" on "Cure for the Common Megasquid cold". He is also a bit of a coward, not liking to face danger and freaks out easily. He is usually the most down to earth character in the entire series.

Luis and C.G.
Luis possibly likes C.G. His high intelligence has caused insecurity and self-doubt with C.G.'s own technical abilities.

Luis and Ethan
Luis and Ethan have a nerd-jock relationship, with Ethan trying to get Luis to become more bold and adventurous. They could also be seen as a comic duo with Luis being The Straight Man, and Ethan being the goofball.

Luis and Emily
Emily and Luis are best friends, they often help each other during the mission "Cure For The Common Megasquid Cold", "Shallow Pals" and "Sweet Home Pangaea II". They show no romantic interest in each other however they work together really well.

Luis and Squibbon
Luis usually sees Squibbon as an annoyance, but he does care for him.

Luis and C.G.'s Dad
He also has a close relationship with C.G.'s father as they both share the same scientific and intellectual interests. Despite at first being called a 'primitive' by him, along with Emily and Ethan, in "Toratonnage", when a Toraton was on the Time Flyer, Luis accidentally activated the time telecommunicator and met CG`s father. Then, they bonded and helped each other to get the Toraton off the Time Flyer.

Trivia

 * Luis' hair being black and banged is reminiscent of the hairstyle of Son Goku from the manga and anime "Dragon Ball", minus being spiky and sticking out to the sides.
 * Luis is usually portrayed as The Straight Man during any comedic moments of the show, Usually with Ethan or Squibbon as a comic foil for him.