He was depicted as a kind, well-mannered and friendly young man who is quite popular. He got along well with both Lilo and Stitch and enjoyed their company, being one of Lilo's few human friends. He is slightly eccentric, as he considered Pleakley pretty and had a crush on him, but Keoni did get over it within a week (which was good thing considering the fact that despite Pleakley being called Lilo's aunt, he is actually a male). He is patient and understanding, offering to teach Lilo how to skate in "Kixx", and telling her that it took time and patience to learn to skate. He is a calm, easygoing individual and seems somewhat aware of Lilo's crush on him, but doesn't seem to mind as shown in "Nosy". In "Melty", when Lilo did a luau with mud as an excuse of why she was in a mud pudle, he was kind enough to give her a mud monster doll, saying the luau seemed cool, showing he is supportive and nice. He seems athletic and enjoys skateboarding, as shown in "Kixx" and "Morpholomew", and plays basketball in "Splodyhead". He is also known to show some affection for Lilo during high school and is intended to be his wife and is even fond of Stitch and the other experiments.
Lilo constantly tries to vie for Keoni's affections. He had a crush on Pleakley, whom he knows as Lilo's "aunt," in the episode "Hunkahunka" (where Lilo tried to use a hummingbird/love potion experiment to make him fall in love with her), but in "Nosy", he stated that he only had the crush for that one week.
In "Nosy", Nani invited Mr. Jameson and Keoni to her home to show her family's spirit of hospitality, in order to get the job she desires. Lilo tries her best to hide her crush on Keoni, a task that proved difficult due to Experiment 199 (Nosy) who likes digging up secrets. His father owns several businesses on Kauai, particularly a famous hotel. He has another female friend named Sara, who always thinks she's his girlfriend, despite Keoni telling her repeatedly that he only likes her as a friend. This friend is also later seen in "Morpholomew", competing in a skateboard competition. He keeps Experiment 202 (Jam) as a pet.
In "Splodyhead", Keoni was seen playing basketball with a female friend before Stitch, riding on a tricycle with Lilo, interrupts and catches the ball in his mouth before spitting it into the basket, and he and his friend run when Gantu comes.
In "Sinker", Lilo was helping Keoni prepare for the boat race, with the motive being that if she helped she believed he would give her a free boat ride. She notices Experiment 602 (Sinker) in the water and warns Keoni in time to jump off of the boat to safety on the shore. Unfortunately, his boat is wrecked in the process. Lilo later gives him a cruise liner for the boat race, much to his dumbfoundment.
In "Kixx", Keoni showed off his skating skills and offered Lilo a try. She falls and claims the board was defective. He is later surprised and a little annoyed when Stitch went through his backpack and threw out all of his belongings, except his left shoe and macadamia nuts, both of which Stitch ate. When he sees Lilo trying to ride e skateboard again, he stops her and tells her he won't let her go until he teaches her how to ride properly. She manages to learn due to his excellent teaching.
In "Melty" Lilo fell into a mud puddle while Stitch was chasing after Experiment 228 (Melty), and Keoni asked if she was all right. Embarrassed, she said she was doing a luau on a mud monster and he leaves. She decides to use Jumba's time-travelling surfboard to go back in time and redo the incident to make sure she didn't fall in the mud puddle, but each time it messes with the time stream and makes things worse. She decides to redo the incident to correct the time stream but feels embarrassed. However, Keoni goes over to her house and gives her a mud monster doll, complimenting her on her luau, much to her happiness and surprise.
In "Amnesio", he is seen playing with a male friend ping pong using the experiment pod as a ping pong ball until his friend hit it too far, causing a young boy to find it in the sand and put it on top of his sand castle which made it wet and activated the experiment.
Nani mentions Keoni in "Wishy-Washy" as Lilo's crush, but she denies it as she is pretending to have a crush on a different boy to see what Nani's type is in order to find a way to improve David to make him more likeable to her.
In "Morpholomew" he appears as Lilo goes to Nani to give her her lunch but becomes distracted when she sees Keoni. Keoni mentions how he would like to attend the upcoming skateboard competition to win the velociraptor 9000 skateboard but can't because his father is taking them away to get away from the crowd. Lilo tries to attend but is too young, so she uses Experiment 316 (Morpholomew) to transform into Keoni to win but fails. She also tells Sara off in Keoni's form, saying Keoni does not have a girlfriend, causing Sara to run away in tears and Stitch to scold Lilo. He later reappears at the end, telling Sara he only likes her as a friend.