This is a fanfiction, taking liberal use of the Harry Potter world. Harry Potter belongs to J. K. Rowling, who I have to thank for writing this. Not that we know each other. That would be pretty cool, though.

Chapter 1

"Who's that?"
"I don't know."
"Is she alright?"
"Hey, wake up!"
She groaned as the noise reached her ears and she tried to pull her blanket over her head - when she noticed she wasn't lying in her bed.

"Goddammit, James! If I-", she bolted upright, angrily throwing her eyes open and glared at the crowd in front of her, frantically looking for James Potter. Finally spotting him, she jumped to her feet, pulled her wand from her pocket and aimed it at him, with an angry twinkle in her eyes. "James Doe Potter! Write your will, because I'm gonna kill you!", yelling at him like a mad-woman, she quickly fired a jinx at his feet and he only barely jumped to the side. "What the heck!?"
But she didn't let him take a breath and shot another on at him - only barely missing his head. "What? Afraid, [i]Potter[/i]? Because you better be!", she hissed and aimed at his feet again - but this time he didn't react in time and he soon started dancing like a drunk Irishman. "Hahah! Don't worry, I'm not done with you yet!", she howled at him and looked at the crowd, watching their reactions amused.
"Who's that!?" - "Another one of James's girls?" - "I've never seen her!" Such and similar whispers went around the crowd and the dancing boy finally managed to take the jinx off of him and glared at the strange woman. "What the hell is your problem? Who are you?", he hissed between gritted teeth and she only laughed in response and crossed her arms.
"Playing dumb now, Potter? Oh, well, guess it doesn't take much acting skill!", she laughed out loud, trying to ignore the weird feeling that gnawed at the back at her mind. Something seemed.. odd. But she could deal with that later. First she had to pay back that git James!
"Well, if there's nothing more to lose, guess I'll just continue!", she grinned and send another hex in his direction, which he skilfully avoided and - finally - took out his own wand, while glaring at her, clearly not amused.
"I ask you one more time - what the hell is your problem?"
She snorted and pointed at their crowd. "Look who's talking! It's your fault that-", but before she could continue she heard a familiar voice from behind the crowd yelling. "James! What's going on?" The boy shook his head. "Beats me."
"Sirius!", she yelled, jumping up to spot the familiar black head between the other students. "You really need to have a word with that stupid git! I know I said I was fine with-", but she abruptly stopped as the black haired boy made his way through the crowd and stood next to a confused James.
"...what?", dazed, she looked at the two boys who both looked like James.
"Ah!", realization dawned on her face and she laughed. "Seriously? Polyjuice potion? What the heck are you two stupid gits planning? I'll warn you, Sirius, I definitely won't kiss you looking like James!", she grinned and came closer to the two boys and inspected them more closely.
They and the other students looked like her in confusion and her own face darkened with bewilderment. "Wait...", she mumbled, trying to make sense of this. These boys certainly looked a lot like James - but not exactly like him. She would know, since she had spent most of her school years with that boy. "Huh, you guys must have really messed up that potion", she joked half-heartedly as the uneasy feeling in her head only grew.
"Look, I don't know who you are, but somehow you got it all wrong." The other boy nodded and only then she noticed that he did look a bit younger. "Yeah, I'm Albus."
She laughed out. "Albus? Seriously? Like Dumbledore?"
The boys nodded in unison. "Yeah, of course?"
She blinked at them confused and took a step back and let her gaze strife the crowd. No face seemed even remotely similar. Something was wrong.
"Okay, fine, you two had you fun, that's enough now", she grumbled and furrowed her brows. "Is this another of your stupid hexes? Making everybody look different? Very clever, but not clever enough", she added and tried to grin smugly. It didn't quite work.
"What's going on in here? Potter, what did you do this time?", a female voice butt in between them and the girl turned around, smiling relieved. "McGonagall! Those two probably stole a-", she closed her mouth as she saw her favourite teacher looking... about a 100 years old.
The older McGonagall came closer and inspected the girl from top to bottom. "And who are you?"
The girl shook her head in disbelief and looked back at James and... whoever, urging them with her eyes to stop with this stupid joke.
"Professor McGonagall, I'm sorry, I think those two put a weird hex on me, everything looks so... strange", she shrugged her shoulders helplessly, having no suitable explanation.
"Your name and house, young girl", the older woman simply asked and she smiled at that, having always liked her no nonsense attitude. "Lynn McKinnon, Gryffindor, obviously", she sighed, thinking that maybe the two did something to her as well. "...McKinnon?", the older woman cocked her eyebrow curiously, but then looking at the curious crowd in annoyance. "There is nothing to see, go back to your dorms, this instant!" Most complained about that, but left nonetheless and soon she was alone with the Professor and her two best friends, who played a rather tiring joke.
"Well, Miss McKinnon, this is a very interesting story, but as the head of the house I know all Gryffindor students and you are not one of them."
The sighed in response. "Okay, guys, seriously? What did you do? This is kinda stupid, I really don't have the time for this."
She turned around and glared at the younger one angrily. "And I really would have thought better of you, Sirius." The boy frowned and looked at his brother and then back to the Professor. He certainly didn't understand why that girl called him by his brother's middle name. "Miss McKinnon, if you would follow me. Mister Potter and..", she sighed, obviously being used to this, "And Mister Potter, go back to your common room." Lynn looked at the two boys who, rather obediently, turned around. "Don't tell me he actually changed his last name!" The woman didn't answer, but simply continued walking down the halls towards the headmaster's office.

Once inside, things made even less sense. Instead of Dumbledore greeting them, it was a man Lynn had never seen in her life before.
"Ah, Minerva, who do we got here?", the man asked curiously and offered them a seat. "Sir, I saw this girl just now in front of the Great Hall, arguing with James and Albus Potter."
The man smiled at Minerva, waiting for her to go on.
"And...", the woman hesitated and Lynn could see how her eyes darted up to the portraits of previous headmasters for a second. "She says her name is Lynn McKinnon."
The man sitting in the headmaster's seat, still smiled at her, waiting for the problem. The woman sighed and removed her glasses. "Lynn McKinnon was a very bright student."
Was? ...was!?
"And she was the sister of Marlene McKinnon."
The man's face lit up and he smiled. "Ah. I see. Thank you Minerva, you can go now." The woman simply nodded and quickly left the girl alone with the strange man. "Uhm..", Lynn squirmed in her seat uncomfortably, not trying to make eye-contact. "Okay, this is kinda weird, but, who are you?" The man smiled at her, too, and she was starting to think that all he could do was smile. "I'm the current headmaster of Hogwarts, John Smith."
"But..", she finally looked at him. "Dumbledore is the headmaster!"
"I'm afraid that's not quite true," a voice chuckled behind her and Lynn could feel her body relax in instant relief. "Dumbledore! What is going.. on...", she turned around and stared at the portrait of Albus Dumbledore.
"Lynn McKinnon? How precarious", another voice injected, sounding almost bored. She turned around and saw the face of... "Oh Merlin... Snivelly!?" The man emitted a strange sound, that seemed to a mix of disgust and shock. "The name is Severus Snape, previous headmaster of Hogwarts, Miss... McKinnon", he said and leered at her.
"H-headmaster!? Ahahaha, oh my god, Snivelly is... was... oh god..", the girl burst out laughing and had to hang on to the chair as not to fall down and it took her several minutes to calm down. "Oh, god, I really have to hand it to them, this is definitely the best prank ever!", she grinned and turned back to the "headmaster", wanting to hear the rest of it. "So, is there anything else? Did Voldemort become a monk? Did the Ministry abolish the auror department in favour of petting zoos? Come on, give me more!", she grinned and eagerly leaned forward.
"Miss McKinnon, I am afraid that this is not a joke. We have the year 2021. Voldemort is long dead, as are...", he looked up to the the portraits and smiled. "..the former headmasters Albus Dumbledore and Severus Snape."
She snorted and shook her head. "Yeah, right, that's why I just saw James Potter out there."
"Oh, there is certainly no doubt about that. James Sirius Potter is indeed a student of Hogwarts." She laughed out. "James Sirius? Are they so much in love that he changed his middle name?"
"James Sirius Potter is the son of Harry Potter and the grandson of James Potter and Lily Evans."
"W-what?" She let out a laugh. "You're trying to tell me that James and Lily had a child? Please!" The headmaster shook his head. "I'm afraid it's the truth."
"I am Lily's best friend! I know her and she would have NEVER gone out with James!", she shrieked and jumped up, not registering the humourless laugh behind her. "Miss McKinnon, I have no reason to lie to you. It is the year 2021 and if I'm not mistaken, you somehow managed to travel 45 years to the future."
She slowly sat back down again, trying to make sense of this. Finally, her face lit up again and she smiled at him, smugly. "Alright, if that's the truth, then please let me meet James, Lily and Sirius! I would give you a lot of money to see them old!", she laughed, just trying to picture them balding or with wrinkles.
But it got suddenly very quiet in the room and she felt dread gnaw at her stomach.
"...Professor?", she whispered as she turned back to her old headmaster, pleading him with eyes to tell her... not the truth, but what she wanted to hear.
"Miss McKinnon... if I remember correctly, you suddenly vanished at the beginning of your 6th year without a trace."
She stared at him with big eyes. "Professor...?"
He looked at her with kind, sad eyes. "They are dead."

She didn't know how or when, but when she opened her eyes, she saw the familiar hangings of her bed in her dorm. Or rather, a bed that looked pretty much the same.
She turned on her side and slowly opened the curtain a bit, to see if any of her new... dorm mates were up yet. It was quiet and their curtains were still closed. She sighed. "James, Lily and Sirius are dead?", she whispered, trying to wrap her mind around it. But no matter how hard she tried, it didn't work.
They weren't dead. How could they? She just saw them. She left Lily in the library, working on some homework, saw her sister in the hall talking to Remus and found James in front of the Great Hall, where the two of them got into a heated argument over something silly and started hexing each other. He had hit her pretty hard, since Sirius coming had distracted her for a moment. And that was when her memories ended and she thought she woke up shortly after that.
But... 45 years in the future? As if!
It was probably just all an elaborate hoax. A hex gone wrong, or maybe even just a really dumb dream. James Sirius Potter, pah! Who would name their kid that? And Snivelly as the headmaster! Yeah, sure! She grinned to herself and thought back to the portrait of their old friend. She certainly couldn't imagine him looking any different than that. So he must be the product of her imagination.
But... James and Lily having a child? She shuddered at the consequences. Hell would freeze over rather than that happening!
Although... she thought back to the "Potter" boys she saw earlier. The one she thought was Sirius did have... green eyes.
She sighed and pulled her blanket over her head. Nope, just a dream!

...because if it wasn't...

Author's Note: My second fanfiction! Or, rather, second first, because I started this at the same time as The Life of a Squib. As you can see, same pairing, though, of course, Lynn McKinnon's background will be a bit different. Or will it? Just treat it as an.. alternative reality. Also, this will probably be lighter than TLOAS. Sirius Black is one of the characters, but I think he'll only pretty much appear a bit in flashbacks or at the very end, this will be mainly about Lynn interacting with the Next Generation kids and trying to sort out this mess and not letting her friends die, somehow.

Enjoy!