Kick is a hard-headed, stubborn, self-tempered 11 year old boy, who would never back down from a challenge. He always wears a stunt suit and stunt helmet. His life's passion (and favored past-time) is extreme stunts. He is shown to have great determination, which occasionally clashes with his temperament. However, despite this all, he has been shown to have a kind heart, performing many kind acts. His damage, which inevitably follows in his wake, is rarely intentional. He has been shown to have quite a tolerance to pain, as of when he fell from space and into the earth's crust without flinching, though when Gunther and Gopi Brave had to pull a lot of thorns from his butt, he yelled out in pain. Brad calls him 'shrimp', or any variation of the above, will generally anger him quickly. However, this is inconsistent, as seen in "Dead Man's Drop", where he took all those comments without showing any change in emotion. He has been shown to have the ability to hold quite a grudge, shown in "Dead Man's Drop" when he yells 'You've made my revenge list Brad! Again!' then adding Brad's name to a list which contains only more times Kick has vowed to take revenge on his older brother.
Despite his bad grades and seeming inability to finish homework, he has also been shown to have a great ability to retain information. This has been shown greatly when he had to do two months of homework in one night, which he did do, though Oskar ate it while he was showing Gunther. Then he managed to finish it all in less than six minutes and turn it into Miss Fitzpatrick, which he succeeded in. Though right after she passed him, Oskar appeared again and ate his homework, implying that Oskar had been the dog that had eaten all of Kick's previous homework assignments.
Kick wears the same clothes every day, his outfit consists of yellow boots, a white helmet with a red stripe down the middle, and an all-white jumpsuit, usually with the collar turned up. In some episodes, it is shown that his helmet has a button on the side that when pressed, a visor will appear to protect his eyes. It is his helmet that he likes most because he thinks of it as a part of his identity. In the end of "Not Without My Cereal", Kick and Gunther are shown on a couch with beards, the result of drinking many Cheetah Chug cans. Gunther is shown with a blond beard as he is blond, and Kick is shown with a brown beard, suggesting he is a brunette. He has blue eyes as shown in "Those Who Camp, Do" when Kick stares at a bear, the screen closes up on his face and we see blue eyes. He is abnormally short for his age, prompting others to make fun of his height with names such as 'shrimp'. Also, his butt is rather big as it always sticks out. He wears white briefs. He is the smallest in his class and he has a gruff manly voice.
Kick is shown to be very skilled in a variety of areas. The most demonstrated is his skill with various vehicles, with him (nearly) instantaneously gaining the ability to drive Billy Stumps' monster truck, as well as the abilities he has demonstrated with his skateboard, bike, and cart. In some episodes, it is shown that Kick has skill in certain types of martial arts like karate, wrestling, boxing, etc.
He is also shown to have engineering skill, as he was able to create a giant mechanical T-Rex with the ability to breathe fire. He appears to have a natural talent for anything that is 'extreme', such as water skiing.
Gunther and Kick display a typical inseparable type of friendship. It was revealed that Gunther and Kick have known each other since they were little in "Trike X-5". They have been known to have fights (as any friends do) but the biggest fight they have had so far was in "Abandon Friendship", when they temporarily moved on to new friends. However, they became friends in the end. They've also drifted apart during "Obsession for Kick", which had Wacky Jackie become enamored with Kick, much to Gunther's displeasure.
Brad is Kick's older brother and his main antagonist. He will often to go out of his way to either cause problems for Kick, or interfere with his stunts. However, there have been occasions where (after a fashion) he has helped Kick, such as the ending of "There Will Be Nachos", which has Brad use Kick's sudden fame to get his party running.
Brianna is Kick's younger sister. She usually annoys Kick and steals his things such as in "Trike X-5". Unlike Brad though, Brianna doesn't bully Kick around, and they having a more loving brother-sister relationship, as shown in episodes such as "Sister Pack".
'Wacky' Jackie (whom earns her nickname from her somewhat insane personality) is Kick's resident stalker. She appears to obsess over Kick in many ways, mainly for his daredevil nature. Gunther also has a crush on Jackie, which Kick used to his advantage in "For the Love of Gunther", but this doesn't appear to have lasted. Kick is mostly tolerant of Jackie for the most part, unless she interferes with one of his stunts. He has also helped her on occasion - "The Gift of Wacky" sees Kick throw her a birthday party upon realizing she has never had one.
Kendall is the polar opposite of Kick - where as he is into speed and daring, she tends to be collected and studious. Despite this, she is considered an antagonist to Kick, but the least threatening. They also seem to share a love/hate relationship, nearly kissing when forced to dance together in "Dancing with the Enemy"; however, they quickly revert back to normal. Additionally, she's the only person to refer to Kick as Clarence, his real first name on a regular basis. However, she's also been known to call him by his preferred nickname: "Kick" in the heat of the moment. Kick actually likes Kendall at times as her inner awesome tomboy personality as prior in "Hand in Hand" when they worked together to get their hands stuck together from the sap. Once they got their hands stuck together they admitted they enjoy their time together and was about to go further as to a confession, almost. In Roll Reversal, Kendall accidentally outdoes Kick in the motocross stunt making her the #1 greatest daredevil of Mellowbrook, making Kick jealous. So he challenges to Kendall to pick a stunt, and she picks Roller Derby. In the episode "Rocked", Kick dreams himself played Rock Callahan, and Kendall is dreamed as beautiful, action-packed and pretty young woman. Because of this, there's hope that Kick may still like Kendall.
In the episode "And... Action!", Kick has a crush on Scarlett. Scarlett has high chances of having a crush on him, too.
Ms. Chicarelli is the secondary antagonist to Kick, and has been shown to dislike most kids. She is more often a causality of his stunts though.
Mr. Vickle is the flamboyant, flower-loving goldfish aficionado in Kick's life. He never intently tries to get in Kick's way (due to his opinion Kick is a nice boy) and as result is the least affected by his stunts. Due to his opinion of Kick, he is intensely disliked by Ms. Chicarelli.