Percy Weasley was doing his night patrol because he's the Head Boy and the Gryffindor Prefect so It's his job to do it. His footsteps echo in the Hogwarts' hallway, each time he turn a corner he expect someone to be here.

That's what happened but in a different manner.. when he turn into a corner to another hallway he froze when he saw the sight before him, you, a fellow Gryffindor and the sister of Oliver Wood, was on the ground, shaking in fear with a insane Luna Lovegood in front of you.

Luna was holding two kn¡ves, standing in front of you, looking down at you with a glare while you were sitting terrified on the ground, Luna thought you were a demon, why? Because she just got insane.

It was literally the night and when Percy saw that, he was in disbelief and shocked, mostly concerned and angry at Luna because WHY Luna is with two kn¡ves in front of you, Oliver Wood's sister.