"What the ruddy ell is that?"

The student, a young Hufflepuff who had volunteered to assist Hagrid harvesting pumpkins, didn't answer. Instead the poor boy stood rooted to the spot, tangled amongst the vines and squashes, eyes fixed on the figure in the trees.

The groundskeepers first thought was that it was a Halloween prank as the students were known to pull.

Except of course it wasn't Halloween. Though someone might be forgiven for thinking it was considering the vast number of pumpkins.

With a whole castle full of witches and wizards drinking copious amounts of pumpkin juice every day; a year-round supply was necessary. They harvested a new batch every week.

So, since it was not, as we have established, Halloween, the question remained…

What the absolute ruddy Hell was that?

It was tall.

That was his first thought.

And as a half giant, Hagrid's definition of tall was pretty damned tall.

It was also unnervingly thin.

Unnaturally tall and unnaturally thin. As if a normal sized man had been stretched out like a glob of taffy. Maybe he had?

Maybe that same process had been what rubbed away its face, leaving behind nothing more than a shapeless white impression.

The 'man?' was dressed in a black suit, perfectly fitted to its strange body and before the groundskeeper's eyes he seemed to flicker in and out of focus behind the strange fog that hovered around him.

"Miles," Hagrid called to the young boy gently, his gruff voice calm even if he was freaking out. Years he had lived by this forest, many nights he had walked into it alone, unbothered by its dangers, not the least of which were his own spider friends. Never had anything inspired fear in him like this strange man was doing. "Maybe, uh, maybe we should head back up to the castle?"

The boy did not answer, still paralysed with fear.

In the trees the suited man was now closer, he hadn't moved as far as Hagrid could tell, he was just closer.

"Miles?" He tried again, more urgency in his tone. The half giant wished he had his umbrella with him, the concealed shards of his wand still stashed inside of it. He was legally allowed to perform magic again now that his name had been cleared but he had gotten used to his umbrella and felt no need to switch back to a regular wand. In retrospect he should at least start keeping it on him at all times like most other wizards did.

He simply wanted anything that could be used to defend against this ever-approaching figure or to perhaps signal the castle for help.

Miles probably had a wand on him but the poor child was going to be of no use, frozen in place as he was.

The tall thin creepy man was now at the tree line and inching ever closer.

Miles had begun to sob.

"Alright," Hagrid decided, preparing to grab to boy and carry him. "We're going to run for the castle."

The boy shook his head, "We won't make it. He'll get us."

"We'll see about that."

They never did get to see about that.

The figure was two meters past the tree line and still edging closer to his terrified quarry when a strange rumbling sound erupted from within the trees followed by a high-pitched mechanical squawking sound.

The keeper of keys and his young pumpkin picker assistant watched in shock as a rather dilapidated but happy looking (it was enjoying the wild life) Ford Anglia sped out of the forest and mowed right through the mysterious figure, driving it back into the trees, long limbs splayed across its front bonnet and roof.

"You know," Hagrid muttered, blinking in surprise once the cars rear lights were out of sight, "I'd forgotten that was in there."

…

"Did you hear? Hagrid is moving into the castle. He says he can't sleep in his cabin anymore."

"And he's refusing to go into the forest on his own."

"I heard he's taking private defence lessons from professor Lupin."

"Miles still won't tell anyone what happened."

"Hey, did anyone ever figure out what happened to that boggart that went into the forest?"

Slender Man, by popular demand.

I found multiple versions of this myth with slightly different appearances and behaviours so I tried to keep it as general as possible.

Note on the previous chapter; someone pointed out there is a Dumbledore vs Gandalf; Epic Rap Battle and I am now fully willing to accept their rap rivalry as the reason for Dumbledore's fear.