Theo Gauthier is a member of the eighth grade. He came to Kadic in the middle of the semester. He was first seen in the episode Claustrophobia, during the late afternoon soccer game between Ulrich's team and Herb's team. He immediatly began flirting with Sissi, and because of this Herb immediately began despising him. Herb's memory of this was erased by a Time Reversion, and, luckily for him, Theo's was too. At the end of the episode, Theo offered to walk Yumi home, provoking jealousy from Ulrich. Theo is not seen after this episode because of the non-linear plotline of Season 1, and he is seen making only a few cameo appearances in Season 2, Season 3, and Season 4 possibly because the writers decided to introduce William as Ulrich's competitor for Yumi's heart.
Theo was voiced by David Gasman.
