Gunbard

Gunbard is Yucie's adoptive father as well as Queen Ercell's ex-lover. He's also the hero who completed the Eternal Tiara known as Courageous Gunbard.

He's shown to be a loving, kind, but somewhat doting father to Yucie.

Personality
His personality varies on time:

During his youth, an energetic persona, combined with a caring attitude.

Before leaving for his quest, he has a serious streak.

Many years later, he retained his energetic persona, but became an overprotective and overpampering to his daughter Yucie. But in battle, he's known to be serious.

Appearance
During his youth, he has longer hair, clean face and quite strong build.

Over the course of his quest, he retains his look, but his body became buffed with countless battles he experienced while claiming the stones needed for the Eternal Tiara.

After leaving the castle brokenhearted, he started growing his hair back.

Many years later, he cut his hair short, grown beard and mustache.

But regardless, the only physical appearance never changed are his slant eyes, which made his eye color mysterious.

Background
In his past, he was Queen Ercell's personal guard and the two eventually fell in love with each other. Upon learning of then Princess Ercell's arranged marriage, Gunbard hurried off to collect the pieces of the Eternal Tiara to become acknowledged as nobility. Once he returned, he would formally propose to her. Unbeknownst to him, Ercell's father had became ill and believed to be at death's door. As his supposed final wish, he asked Ercell to marry the man who had originally proposed to her. Ercell, reluctant and saddened, agrees. Gunbard had indeed returned with the completed Tiara, but it was too late for his beloved had already been married.

A devastated Gunbard leaves the palace behind forever and some time later is sent off to war. After the battle, he sees a glowing light descend from the sky. He rushes into a clearing to investigate and finds an infant girl.

He adopts the baby as his own and names her Yucie. He quits being a knight, focusing on taking care of his daughter.

Before the conquest
He was a commoner living near the boundary of a forest and Lord Drago's lake. He also has a relationship with Queen Ercell, when she was a Princess, but their nobility differs, him bring a commoner and the woman he loved, Princess. One night, he promises her to marry after he conquered and completed the Eternal Tiara, the stuff of legends, so that he became a noble and marry her. Before leaving, he gave her a ruby-studded ring, in exchange of the former King's sword and shield, then shared the night together.

Conquest
He went to the different realms, meeting it's respective leaders. He firstly got the stone representing Human World, then he went to Heavens, defeated the guardian and took the stone representing Heavens, he also went to the Demon World, defeated the guardian and took the stone representing Hell, he also went to Fairy World and completed the quest to take the stone representing the Fairy World, he also razed a haunted building in the Spirit World, and took the stone representing the place. He went to a forge and built the tiara using platinum, unknown metals and the stones.

Return and meeting Yucie
After many years, he returned to the Kingdom, where he presented it to the King. He saw Queen Ercell, now married to the King. Despite being hurt and seeing his gift gone in her finger, he finished the ceremony and left the castle, leaving the armor and sword outside.

Many months later, he was on the front lines, fighting enemies, he kills a mage near a ruined town, when he saw a flash of light coming down in a forest near a ruined castle. He ran to it and saw a baby in a basket. The baby was Yucie. He returned on the camp, with his men rejoicing, some despite being heavily wounded in the battle. Some time, he quits being a knight and finished the house he planned. In this time, he met Cube and made him his servant.

His find of Yucie was like the setting of Princess Maker characters, found as an infant, raised by the finder and the main pathway towards the character's choice in life.

Present
He accepted the fact that her daughter stopped aging at age 10, but he raised her overtly, overprotecting and pampering her, much to her daughter's annoyance. He gave her a feast, much to her dismay.

When Yucie tells the news of her being a Platinum Princess candidate, he was overjoyed and let her and Cube attend the Princess Academy. During her school break, he spoils her with food and items, to the point of giving her energy drink to ease her stress.

When Arc starts finding him, he welcomed the notion. And when they met, he just welcomed the Prince with warm reception, also answering his questions.

But when Diabolos attacks the Human World, and Arc was injured, he went to the castle, and tries to delay the Prince's curse. Also, he opened a warp towards the place where the last stone is.

After the battle, he appears on Yucie's dream, cheering on his daughter.

Yucie
His adopted daughter. He found her during the aftermath of his battle near a ruined castle. From then, he quit being a Knight and raised Yucie the way he knows.

Cube
It is unknown why or how Cube was made servant, but he treats him like the way he treats anybody.

Queen Ercell
He has a former relationship with her during their youth, but their nobility differs, him being a commoner, her being a Princess. He promised her to become a Hero and raise his rank by completing the Eternal Tiara so that he can marry her. But she married the future King instead. Heartbroken, he continues being a knight, but quits after finding Yucie. During the time of Arc's injury to Diabolos, he has nothing to say about her, and focused on healing the Prince.

Prince Arrow/Arc
Arrow/Arc goes to find him, in order to ask him who he really was. Their relation is unknown. Prince Arrow suspect that he was his father, the reason he left the Palace to find him. But the old man just rebuffed him, telling him that the late King is his parent.

Trivia

 * Gunbard doesn't like crowds, and that's why he doesn't go to festivals such as the Harvest Festival.
 * He also has slanting eyes, which was mistaken to be blind. But the only time his eyes opened wide, was during his campaign near a destroyed castle, when he spotted a light going down to the forest.
 * Just like Simon from another Gainax anime, Gurrenn Lagann, he is a tragic hero when comes in love life. But unlike Simon, his love married another.
 * He also is a worrywart, to the point of thinking to create a potion for her stressed daughter, hinting that he can do alchemy, besides his other abilities.