Klaus Revelle

Sir Klaus Revelle is a royal knight of the Kingdom of Egalstria. He was the one in charge of the expedition to kill the Plague Dragon, and was the former wielder of the enchanted spear known as the Omnilanze.

Early Life (Birth - 19)
Klaus was born into the prominent noble house Revelle, which was traditionally a family of great knights who were tasked with protecting the royal family and the Egalstrian monarchy. As a child, Klaus was given intense martial training, especially with the spear.

As the kingdom fell further into disarray, most members of house Revelle were sent out to maintain order in the kingdom's various territories... Except Klaus. Klaus was given a special mission by King Heinrich, to slay the legendary Plague Dragon, which had once more returned to the land. With his family spear, the Omnilanze, in hand, he was given a team of heroes to help him slay the dragon.

Plague Dragon Arc
Klaus left Pietravale with a small team, including such people as Augustus Invictus, Amaranth li Astellia, Igni, and more. Over the course of the journey to the southlands, now called the Plaguelands due to the devastation caused by the Plague Dragon, he grew close to Amaranth and the two children of the group, Hana and Lycoris, becoming known to them as "Uncle Klaus", especially to Lycoris.

When the fight with the dragon actually happened, Klaus pulled his weight well, but when the dragon was struck down, he couldn't bring himself to finish it, for it would mean he too would die. So, Hana took his place in the weaves of fate and sacrificed himself to destroy the Plague Dragon.

After this, Klaus went into a deep depression, and began heading back to Pietravale.

Return to Normalcy
On the way to Pietravale, he met a woman named Olive, and the two fell in love. When Klaus and Olive returned to Pietravale, Klaus presented himself before King Heinrich and asked what his punishment would be for not ending the dragon with his own hands. However, there was no punishment. The King forgave him, and pressed for Klaus and Olive to marry for the sake of public order. However, Olive couldn't bring herself to do it, as she had unresolved family baggage back home.