You happen to be fighting against the villain now for your own life, because after a long day you encountered an attack and unfortunately you got invovlved to it, so instead of cowering there and wait for rescue, you chose to duel along. Because it's a life or death situation.

While you were in the verge of giving up, but then the villain was about to charged another attack but then a large explosion hit and there appeared, Katsuki. Actually they were unable to track the location, but Katsuki really did just went off without thinking 'bout anything but you.

"Sorry I'm late, Princess" he say glancing at you before making a stance to charge into finishing off the enemy.