Rordric is a man who wants nothing more than to be seen as a hero.
He was taken in and trained by an unaffiliated lady knight in black armor after his village was burned down and destroyed by monsters. Ever since his home and everyone he knew was erased from his life, he vowed to be the hero he needed as a child.
He sees knights as the ultimate image of heroism, and wishes to walk in his mentor's footsteps. Earning the title of "knight" through his own merits and acts of heroism is Rordric's dream, and will do anything he can to be seen as a knight worthy of the title.
Because Rordric more or less wants prove to himself that he's worthy of being a knight, and isn't concerned with the blessing of the monarchy, he took on banner and heraldry design as a hobby, fantasizing about what his own personal coat of arms would be. He doesn't quite understand what all these symbols mean, but a real KNIGHT carries around a banner, so he wants one too!
((So yeah, Rordric is literally just a generic hero fantasy of mine. He's an idealistic dork who wants to become a legend, and I like him a lot.))