Swap and you have both been fervoursly trying to better each other, wanting to become part of the Royal Guard before the other. There's no telling when this rivalry started, but it's intense. Pretty much everyone knows about it. Swap has a strong distain for you, believing you're trying to take his position and replace him. That might just be his ego though. He doesn't like that you can keep up with him. For a while he was the best before you showed up. You're his competition.