Harry was sitting cross-legged on his bed reading through the potions book,  he was reading instructions on how to make a healing draght when he saw something else scribbled on the page. Sectum sempre - for enemies.
Wait that wasn't a spell Harry had heard before. He could already hear Hermionie telling him to not use a spell he didn't know the effects of but maybe it was a harmless jinx.
Yawning, Harry closed the old book and cast a quick Tempus to check the time. 9pm. Well I guess he had time to complete a potions essay.

Speaking of potions Slughorn had said earlier that he wanted to see him at some point. Well curfew was in one hour so Harry decided to ditch the homework and go see him. Getting up from his bed Harry stretched and then tugged on some old trainers.

It was a quick walk from the dungeons to slughorns office and Harry walked through the corridors with the familiar unease that seemed to stalk him nowadays. Pushing it aside, he reached slughorns door and knocked loudly on it.
Slughorns face appeared in a tiny window in the door after Harry knocked and then the door was pulled open.
"Ah Harry my boy, what brings you here at this time of night?" He asked after inviting Harry in through a gesture.
"You said you wanted to talk to me sir"
"Oh yes! Almost forgot myself well I wanted to congratulate on your improvement in potions. It's really quite incredible"
"Oh thank you sir, but it's really not that"
"You're very much like your mother, very humble." Slughorn interupted 'She gave me a fishbowl once, and there was a flower in it. A lily of all things, and overnight it transformed into the most beautiful fish. She had great talent that way but always was so humble about it." Slughorn regarded Harry and then continued. "The fish lived for years until one night when it disappeared all together" Slughorn took a deep breath and stared at the same spot for a few seconds without blinking.
"One of my favorites students"
Then he blinked and gave a pained smile to Harry.
Slughorn cleared his throat "anyway I have a little something to celebrate, funny I had been saving this for another occasion but I suppose now is as good a time!"
Slughorn pulled out a dusty looking wine bottle. He pulled out the stopper and poured some of the liquid into two brandy glasses.
He held one out to Harry who took it carefully.
"To your mother"
Harry smiled sadly and clinked glasses with slughorns saying "to my mother"

Harry then took a sip of the liquid as Slughorn finally exclaimed "oh I completely forgot Harry I have a potions book you may be interested in..Harry?"
Then there was a thud. Slughorn froze. Harry potter suddenly started to shake, lying on the ground. Then Harry started to shake even more and started to choke as white foam started frothing up in his mouth. Slughorn dropped his glass, staring wide-eyed at the boy seizing on the floor in front of him.

"Professor Slughorn!" Another voice called out from behind the slightly agape door.
Slughorn was still staring and Harry was begining to turn blue.
"Professor someone has been stealing the potions ingredients..." Snape trialed off. Blinking once Snape then rushed over to the potion ingredient boxes and started shifting through them.
"Slughorn snap out of it and do something the boy is dying!"
Then when he found what he was looking for Snape rushed over to Harry, dropping down on his knees and stuffing an ingredient into Harry's mouth.
"Breathe, don't die you idiot boy" Snape snapped.
Then Harry breathed in harshly, but his eyes were still shut.
"That boy almost choked to death and you didn't even move. At least Help me get him to the hospital wing" Snape said sharply.
But Slughorn just sat down heavily onto an armchair in shock.
Snape sent a death glare to Slughorn and went about getting Harry to the infirmary.

-----------------------------------------------------------

Harry cracked open his eyes and then squinted them shut again.
Ugh why is it so bright. But it shouldn't be bright in the dungeons. And the bed sheets shouldn't feel so crinkly. Squinting his eyes open again he saw blurry white walls with large windows and, Harry sighed, he was in the infirmary.
Harry sat up slowly and reached out blindly for his glasses when he felt a cough coming up.

If felt like there was mucus in his throat so he coughed it up and immediately winced as pain flared up in his throat. Although the pain was bad the urge to cough overwhelmed it and he coughed again only to finally cough up what was stuck in his throat but it made the pain worse.
"Mr Potter drink this, it will soothe your throat" Harry heard a familiar voice say.
A glass was pressed up to his lips and Harry took a sip of it and almost sighed in relief. It felt like cold water putting out a flame.
"Drink the rest of this and then you're free to go."

Harry wracked his brain thinking of what exactly had lead to this untill he remembered seeing Slughorn, talking about his mother and...Drinking. There must have been something in that drink to have done this. 
Finishing the glass full of whatever potion it was that helped soothe his throat. Looking down he saw himself in the hospital Pajamas and shook his head. Why does this always happen to me? He thought for a second about how he had gotten changed out of his clothes and then decided to not think too much about that.

-----------------------------------------------------------

"Harry!" A voice called out and Harry turned to the voice who belonged to Hermionie.
Harry smiled and all of a sudden she was running towards him with arms outstretched. Harry braced himself.
With an ompf Harry wrapped his arms around her and scrunched up his face as bushy hair pushed up against his face.
"Hi" Harry said into the face full of hair.
"Oh I'm so glad you're okay!" Hermionie said, relief clear as crystal in her voice.
"Yeah I'm okay" Harry reassured
"Let's go to breakfast your boyfriend's been fretting"
"More like ferreting!" Ron said, appearing from out of no where.
"Ron!" Hermionie exasperated and tried to frown but a small smile started to spread before all of them burst out laughing.

And as all three of them laughed the next evil plan was being conjured, from a brilliant mind in the great hall itself. Little did Harry know Draco was going to be the next target and little did anyone know what was in store for the wizarding world.