Antoine Jean Pierre (アントワンジャンピエール) is the King of Francia. Yuuri and the rest go to Francia in Episode 38 to look for one of the forbidden boxes. Jean Pierre is afraid of war and doesn't want to get involved in any kid of conflict.
Yuuri, Gwendal, Yozak, Murata and Wolfram pretended to be peddlers who had something wonderful to sell in order to get close to the King. Laila, the king's guard, attacks them to prove they're not mere peddlers. In the end, Antoine decides to help them.
Antoine and Laila later get married in Episode 83.