You insulted someone else. You know that you insulted someone else, and did it specifically because it was insulting. And they responded with a duel challenge. They felt that it was such a horrible insult that they decided it was worth putting their life on the line to prove it. Multiple people did so. At least one of the ones who challenged was even of equivalent station: A duke and a general. So there's no grounds for refusal based on social station. (i.e. a 17 yr old nobody challenging a king.) You claim that your character is an expert swordsman, so there's no grounds for refusal based on a swordmaster challenging someone who doesn't know which end of the sword has the pointy bits.
Why should Creed duel? Because if he doesn't, then everyone in the University will consider him a coward. Since there's no obvious reason why he shouldn't duel after having done what he did, they have no other choice.
So, yeah, you don't have to duel. That's your choice. I'm just telling you what will happen if you don't. Your character will forever after be know to everyone in the Dwilight University as someone ignorant, loudmouthed coward.
