He slipped inside the locker room, and tripped over something. Someone.
He used his phone light to look around. There was a group of men in the locker room who had been bound with rope and gagged with basketball jerseys. All of them were dressed as knights.
Well, what do you know?
Harry removed the men's gags and used his knife to saw through the ropes.
"We are most grateful, sir!" one of the knights said, and the others quickly agreed.
Harry was still working on the second knight's ropes when he heard the men gasp, and looked up to see—
What are those? And what are they holding?
Moments later, the demons had Harry bound and gagged along with the rest of the knights. Their beady red eyes glowed in the once-more dark locker room, as the demons stood ready to deliver an unknown and probably unwelcome fate.
(How unfortunate for everyone! Try again?)