The Crystal Clear Reflection of the Lake

Cass wiped her hot brow. All this running around a lá Auror mode had really tired out. Happy that the fun was almost finished, and after this Clue, one final one remained, Cass placed the penultimate Clue scroll near some brambles, facing the front doors of good ol' Hogwarts.
As she walked away, very plain to the eye, anyone could have seen Wonder where pumpkin juice comes from?
Simple enough.

Raven was wondering what exactly to say to Pia when he found her. He really wanted to ask her why should put a clue in MOANING MYRTLE'S BATHROOM! She should know it's a girl's bathroom and that boy's were not welcome there. Shaking his head he spotted the clue the Ravenclaw girl had left. Picking it up he read it and wondered why this one was so much simpler than the others. Shrugging he headed for the pumpkin patch.