The boy is 15 years old, and in the virtual world... he means business.
In the real world, he is just tired from school, doesn't give a damn to the teachers, and still keeps getting high scores... He is friendly to his classmates though.
In the game, he is highly amused, playing with his friends, and battling in the battle arena.
Leon was always bored in life, from being bored of crying as a baby, being bored of playing with the toys in kindergarten, to being bored as a student, where he is now. His friends kept him satisfied... somehow, but when that game came out, he was one of the early players to join, and create their character. He enjoys playing, and enjoys talking about the game in school, even if its right before the teachers' eyes... ouch... He has a big sister, which also plays this game, but she is not totally addicted as he is...