He still first need to throw him a glove at his face.

Swordfight

D-d-d-duel?!

Of course MC is going to accept the duel he can obviously say no since he doesnt have any obligation to accept, and of course sueun will not be against blondie using her as a trophie that will be given to the winner since she will like the fact that the guy she kinda likes is fighting for her and once again of course MC is not going to lose against blondie in the duel only to make him grow stronger so that his and the girl's feelings grow bigger for each other, oh and by the way of course the other girls will not get involved in one way or another.

1v1 me Beyblade you dick, I choose Sebastian Vettel.

Of course the MC will also be dumbed down and accept the duel(lul).

The best retort mc can say is : "only children duel like that ask her if she agree to be considered like a trophy."

I always think its so funny when authors write their characters this way. Like the characters do realize that just laughing in his face and then walking away would be the power move?