This whole thing started because she kept quiet about her feelings and then it got exposed and it hurts people. THEN SHE REPEATS THE SAME THING WITH A DIFFERENT PAIR.
I love how the guard acts all high and mighty, trying to strike his horse and went "it's a prank bro", and turns out he was only that brazen because he thought his sugardaddy will protect him if the duke go for his neck.
So she started it. I mean, yeah he shouldn't talk shit, but that's not enough shit to account for that amount of torture. Hell, tripping him that one time should've been enough for that level of shit talk.
Dude got artillery for days, powered suits for days, and point supplies for—again—days. He still insists on using mediocre stuff against clearly a boss-level monster. That "manuke" thing clearly isn't just about his lack of mana.