Jeremie Belpois (also spelled Jeremy Belpois) (pronounced as "Jerr-mee Bell-Pwah") is the main protagonist of Code Lyoko, and a Lyoko Warrior. Jeremie is 11-12 years old at the start of the series, but with the intellectual and scientific, gifted and talented mind of someone far beyond his years. He acts as the guide in Lyoko, since he is able to run the computer that no one else can (besides Aelita). It is also Jeremie's discovery of the Supercomputer that commences the group's quest to materialize Aelita into the real world, which is revealed in X.A.N.A. Awakens. He's noble, but sometimes has a short temper. He is also the most vulnerable to being possessed by X.A.N.A., the reason for his susceptibility is unknown, but it is believed that his lack of experience in fighting X.A.N.A's monsters on Lyoko may contribute to this.
Jeremie is the computer genius whom operates the Supercomputer and allows the interface. He's also the leader of the Team, and shows good tactical skills even under pressure. As the most level-headed, he keeps the infighting within the group to a minimum. He can even get a bit authoritarian, despite being the youngest. Jérémie is one year younger than Ulrich and Odd, having skipped a grade. He has more than a crush on Aelita, and it's largely this motivation that keeps the Team going in time after time to shut XANA down.