Antoine is a Mobian coyote with mainly beige fur with blonde countershading on his face and around his eyes and belly. He also possesses blue eyes and combed blond hair. For attire, he wears a blue Royal Guard uniform with red trims and large, golden epaulets, as well as high, red military boots. 

Antoine is clumsy, cowardly, self-centered, vain, pompous, and has an excessively high opinion about himself. However, his clumsiness can sometimes prove to be useful, allowing him to discover secret passages and other hidden subjects purely by chance. Very French-oriented, Antoine's most characteristic feature is his French accent and tenuous grasp of the English language, which makes it difficult for others to understand him, or vice-versa. This often causes him to get ridiculed by Sonic and his friends, though he typically does not catch onto it. In order to win the affection of Bunnie (whom he calls "the love of his life"), Antoine tries to pretend to be someone brave and ready to defend himself. However, when it comes to facing real dangers, Antoine often hesitates and is unable to face the challenge ahead of him. Once his cowardly nature surfaces, Antoine often screams out of fear and descends into a babbling, trembling mess.