Gunbard found the infant Yucie after a battle and raised her as his own. He was once a legendary knight, and is often referred to as "the Hero Gunbard." But now he spends all his time doting on Yucie and is always cooking her large amounts of food which she does not always appreciate. Gunbard, fondly called "Papa" by Yucie, may have a mysterious connection with Queen Ercell as well as one to the Eternal Tiara itself.
It is found out later that he is the one to have completed the Eternal Tiara, which was then separated in different parts and scattered around the different worlds. At the same time, it was found out later that he was the first lover of Queen Ercell. This is also the reason why he wanted to complete the Eternal Tiara, so that he can gain a title in order to propose to Ercell. However much to his surprise, when returned upon the completion of the Tiara, he found out that Ercell had marry the King, who was Arc's biological father.