Surely not, but Severus hadn't lived this long by discounting his instincts. So with a deft slash of his wand, he created a magical barrier encircling the tower, just a few feet below the parapet. Anyone attempting to leap off this edge would find themselves bouncing off his protections a short while later. Not to mention the alarm it would set off for him, and only him. By the time a suicidal student, Potter or otherwise, figured out how to break through the enchantment and continue their perilous downward journey, he should be up there and more than ready to prevent them from their attempt.

Or that was how it was supposed to go in theory anyway, and it was a worn-out Potions professor who plodded to his quarters later that night, praying to all the gods that Potter stayed put for once. He was exhausted.

The next afternoon, as it shaded toward evening, Severus crinkled his nose in annoyance at the clamour emanating from his chambers. If Peeves had found a way into his study again... Quickening his steps, his hand was on the knob when he finally realised what it was. The Tower alarm...

The Potions Master whirled and made his way to the Astronomy Tower so quickly, it almost looked as if he'd Apparated.

Of all the things Harry expected from jumping off the top of the Astronomy Tower, it was not stopping five feet below the edge on an invisible barrier. The impact drove his breath out of his lungs with a painful whoosh, and he rolled over on his back, squinting against the rays of sunlight still filtering past him, as he fumbled for his wand. There had to be a way past this. A little voice in the back of his head asked if it was worth it, finding another way, but he ignored it, fingers scrabbling through the folds of the invisibility cloak. One fingernail bent back almost all the way, causing a thin rill of blood to trickle down his hand, but he ignored it as he seized his wand, triumph sizzling through his veins.

Then he heard it. Footsteps, loud and approaching. Eyes widening at the sight he must look, Harry flung the invisibility cloak over himself, scrunching down in it just as a shadow fell over him.

"I know you're there," his Potions professor's acerbic tones filtered down to him. "I put the barrier up. Considering you would look far wavier if you were Disillusioning yourself, it must be an invisibility cloak, and since the only student I know with that is a certain Gryffindor...would you like to come out of there, Potter?"

Turning crimson with humiliation and thwarted effort, Harry lowered the cloak a bit, until just his flushed and sweaty face poked out. He couldn't properly see Snape's face, but he thought the man looked angry.

A whispered word later, and Harry was floating straight up, flailing with more than a bit of panic before he tried to recollect the tattered bits of his dignity. Snape deposited him gently on the floor of the tower, and summoned the invisibility cloak the next moment.

"Hey, that's mine," Harry blurted out. Snape raised one eyebrow.

"And you shall have it back when I am assured that you will not use it to cloak any other suicide attempts," the Potions Master sneered. Harry flushed again, shivering a little in his Muggle clothes.

"I wasn't trying to..." he protested weakly.

"Of course not. You always try to leap off the top of the Astronomy Tower before dinner. It provides a bit of exercise," Snape said, scathing. Harry bit his bottom lip. Well, when he put it like that...

"Come on, Potter," Snape said, holding out one hand to help pull Harry off the floor.

"Where?" Harry asked, apprehension pooling in the pit of his stomach.

"The Hospital Wing," was Severus's curt answer.

Shit, Harry thought.