Percy inherited his father's heroic spirit and is eager to be his father's "Ally of Justice." He looks forward to any opportunity to work along side him and is protective of his mother, wanting to become strong enough to protect her. Like Arthur, Percy is willing to help out anyone in need and often looks for opportunities to assist the common citizen.

Unlike his father who is plagued with unfortunate bad luck, Percy is blessed with astronomical good luck. In his support with his mother, Percy falls off of a cliff known to kill people, only to walk away with only a minor cut to his knee, a testament to his natural-born luck. However, Percy greatly dislikes his gift, as it removes all the hard work he should use like any other normal person. He admires his dad simply because his unlucky status always gave him challenges to overcome with his will alone, whereas Percy cannot even stop his luckiness when he tries.

He shares a strong bond with his Wyvern, Ace, whom Arthur found to be Percy's friend while he was raised in the Deeprealms. He is able to decipher the meanings of Ace's roars.