A superbly skilled swordsman who protects his lord as an Imperial Knight, the highest class of knights in Burnstein renowned across the continent. Because he doesn't express emotions, he appears to be a cold character. With his self-imposed strictness, his loyalty to his master Richard is deeper than anyone's. He made acquaintance with Oscar Reaves from the military academy and they are very close friends. Richard inspired him to master the sword. He lives and fights for his friends and will show no mercy to anyone who hurts Richard or Oscar.
As he was friends with Richard before Gevel controlled his mind, Ernest would not leave his side, even after Richard suddenly changed. Ernest resisted against Eliotte taking the throne. He attacked Carmaine's camp with a group of soldiers to seize Eliotte, but was not successful as he was summoned back to the capital upon the news that Oscar Reaves had turned traitor. Carmaine's group prepared to attack Burnstein castle to take the throne for Eliotte. Ernest fought to defend it for Richard, and even fought against his friend Oscar, who was supporting Carmaine's group in taking down Richard.
Before this, Ernest and Oscar both knew that Richard's change in personality was unnatural. Neither of them wished to betray Richard, but they decided that one of them must leave and the other will stay to defend Richard to the end. Ernest only wished for Richard to turn back to normal.
Because he supported an impostor and was in effect fighting in Venzern's favor, Lyell's position as Imperial Knight was removed and he was exiled from Burnstein. Oscar Reaves had requested Eliotte to be merciful with Lyell. Even so, his love for his home country did not change and he would come to defend it if necessary.
At the time he was in the military academy, Ernest was prideful of his strength. However, that confidence was broken by the sword talents of one person, Richard. Richard told him "Your sword is dead," and those words broke Ernest's spirit. It was because his swordplay had no "motive". Richard told him he wanted Ernest to lend him his strength. Ernest made a friend for the first time and at the same time obtained a motive to wield a sword - to defend his friend Richard and the peace of his beloved country Burnstein.
Because he was exiled from Burnstein, he lived in the forest between Rolandia and Burnstein. Wein Cruz came across his home a few times, and requested Ernest to join him and help defend Burnstein as war was upon them because of Wolfgang. Ernest refused, and Wein angrily challenged him to a duel. Wein accused him of being lifeless, and stated he could easily win against him like this. Sufficiently provoked, Ernest struck out at Wein. Wein successfully parried Ernest's blows, and Ernest agreed to join him.
After Wolfgang and Maximillian were defeated, Oscar came to Ernest's home to tell him that his exile would be lifted after one more year and he would be allowed back into Burnstein as an Imperial Knight.