Knights were taught to be gallant, courages and loyal. They had to believe in the Church's teachings and defend the Church. Crowley doesn't believe in the Church at all, in fact he hates it. But when the pretty blue eyed alter boy (Castiel) catches his attention during one of the services that he was dragged to with his fellow comrades, Crowley begins his chivalrous wooing i.e. letting Castiel cross over his coat on puddles and what not. Something sweet and fluffy!