William Dunbar

William Dunbar is a member of Team Lyoko and a ninth grader at Kadic Academy. He is mostly known for being Ulrich Stern's primary competitor for Yumi's heart. Presumptuous and snide, William is commonly treated as a minor adversary to the Lyoko Warriors, despite becoming one in the end.

William arrived at Kadic Academy in New Order because he was kicked out of his old school for sending love letters everywhere. He enrolled in the ninth grade, quickly taking a liking to Yumi. However, due to his jerky attitude and need to outdo Ulrich constantly, Yumi liked him less and less, although it is still implied he has a crush on her.

 

Yumi Ishiyama

Yumi usually talks to Jeremie about her feelings about Sissi, Ulrich, and the others, as seen in Log Book. 

Yumi likes wearing black, and all her clothes (and her hair) are that color. Basically its the american goth look, black sweater, black pants, and black boots. Her season 4 outfit is like her sports clothes. Dark gray blouse, gray pants. She wears the same boots as in season 1-3. She is of Japanese descent, and even did a cultural report at school on her homela

Ulrich Stern

Ulrich Stern is a member of Team Lyoko and the unofficial leader. He is a quiet and shy person by nature, quite the opposite of his best friend, Odd, whom he is roommates with. He is one of the Lyoko Warriors, and one of Princess Aelita's closest friends.

He is voiced by former Broadway actress Barbara Weber-Scaff.

 

Odd Della Robbia

Odd" Della Robbia is a member of Team Lyoko and possibly the most popular among fans for being kindhearted, carefree and funny. He calls himself a ladies' man, but the females he's dated would say the opposite. He likes the color purple, and wears it on most of his clothes. He is one of the Lyoko Warriors and is Ulrich's best friend. He used to like a girl named Samantha Knight (first seen in Rock Bottom), and XANA is his sworn enemy.

Jeremy Belpois

Jeremy Belpois is a member of Team Lyoko, and the brainiac always present. Jeremie has only gone to Lyoko (or attempted to) a few times because he is afraid of the scanners, despite the fact he operates them. However, he can overcome his fear if his friends and girlfriend are in danger. He is Aelita's love interest. His father is named Michael Belpois and it is revealed that he also has a cousin named Patrick.

 

Aelita Schaeffer

Aelita Hopper" at Kadic Academy, is a human-turned virtual being, and the daughter of Franz Hopper. She is the technical ruler of Lyoko in as much as one exists, is the leader of Team Lyoko , and for the most part the target of XANA's schemes. Aelita is also one of the characters with an unnatural hair color, the other being one of her protectors, Odd. XANA is also her sworn enemy and is after her. She has a relationship with Jeremie