After Harry had finnished listening to Filtch tell him how if he had his way Harry would be spending time in an Iron Maiden (like a cupboard with lots of spikes, very ouch!).
Harry trudged off to detention and had completely forgotten about having his will be done. As soon as he got there Snape through an apron and toothbrush at him with a smile, and said, "You are to scrub clean that mess Mr Longbottom left in front of my desk."

Harry was surprised that it was as simple as that, even though he noticed there were no gloves and that the mess Nevile had left was his entire cauldron of potion which was most likely to be wrong and therefore have it's own side effects.
He had only just put on the apron which was frilly with big purple flowers when.......Malfoy, Crab, Goyle and three other Slytherins walked in.

"What are you doing here?" harry demanded.
"Professor Snape inivted me to observe him brewing a quite unique potion, but oh, I didn't realise you had become the Hogwarts janitor. Later you could come clean out my fire place it's could do with a clean." said malfoy ginning smuggly
Pansy brushed past Draco to comment, "Ooh don't we feel pretty in our ruffled, purple apron. He does look the part though dosen't he."
"Just one thing missing," and with Harry frozen in his horror, Draco drew his wand.......