Author's Note: I think everyone does it eventually...here it is, my attempt at a time-travel fic. While some cliches will undoubtedly stay the same, I've tried to put an original spin around it, as Hermione works to change the future while living in the past.
Severus shifted awkwardly as he walked into Diagon Alley with Lily. He didn't really want to be out shopping as it only reminded him that he didn't have money for the same kind of frivolities as his only friend. This was made even more clear when the entire purpose of the trip was for her to buy a magical watch with her parents' permission when she had complained about how her muggle watch malfunctioned at school. How Lily had convinced them he had no idea since watches were given to young witches and wizards when they turned of age, but he understood from their perspective - he could hardly imagine denying Lily anything.
Which is exactly how he found himself walking into Prewett Brothers Charming Clockwork, despite it being the warmest summer since 1947. The redhead had none of her reservations, as she scurried up to one of the cases with a squeal. "Look Sev! This one has all the moon phases and planetary shifts as well as time!"
"You're just cross that Barty's ickle girlfriend broke your record from first year." Severus teased despite himself.
"I am not!" Lily shot back, hands on her hips. "I just think it'd be handy to have a reference."
"I find an arithmantic timer to be more useful, myself." Another voice put in, interrupting the conversation smoothly. "Especially for higher potions levels."
Severus glanced up in surprise at the strange voice, berating himself. As usual, he was so focused on Lily he hadn't thought about his surroundings. This time, however, there were no Marauders with wands out to make his life miserable, just a girl with a mess of brown curls behind the counter. He was about to sneer and say something cutting about people who couldn't do the timing in their heads, but Lily cut him off, turning to the girl at the counter with a smile.
"That sounds brilliant!" Lily said excitedly. "I can never compete with Sev in Potions…" She gestured to the greasy-haired boy with a gesture of her hand. "He can do all those calculations in his head. Maybe I could actually keep up with him something like that!"
"Aren't you a little young to be working here?" Severus asked as coolly as he could, since he could hardly insult Lily after what she had said about the timer being useful. He was shocked when the girl didn't take offense or recoil from him. Everyone recoiled when he spoke to them like the idiots they were.
The girl didn't even blink, she just smiled at him as if she found him amusing. People didn't smile at him. "I'm just working in the shop for pocket money over the summer before I go to Hogwarts for the first time." She paused awkwardly, a strange expression crossing her face. "My...parents...thought it might be a good way for me to meet people my own age here, but you two are the first people I've met under thirty in the shop."
Severus arched an eyebrow in suspicion and moved up to the counter, leaning on the glass gingerly, next to Lily, whose green eyes were sparkling at the stranger as she let out an excited squeak. "Hogwarts hasn't had transfers since the fall of Grindelwald."
"I know." The girl smiled with perfectly straight white teeth back at him. "Mum had to go rounds with Headmaster Dumbledore to get me in, after my great-grandparents died."
"Wow!" Lily said, practically bouncing on her toes. "Where did you go to school before? Beauxbatons?" She blushed then, and frowned. "I've been rude. "I'm Lily Evans and this is my friend Severus Snape, we'll both be fifth years at Hogwarts this year. What's your name?"
"I'm...Persephone. Persephone Meadowes-Prewett." The girl replied, shaking Lily's hand. "I'll be going into fifth year too, I'm nervous, I've heard it's very different from Kakistos Academy, where I went in Greece."
"Oh, I'm sure you'll love it!" Lily said, excitedly. "Sev and I will make sure to take care of you and teach you all the tricks to get around and who to avoid, won't we, Sev?"
"Not that it's hard." Severus sneered. "Potter and his band of misfit Gryffindors make themselves exceedingly obvious."
"Avery and his gang of Slytherins aren't any better." Lily replied, distracted by a watch in the case, which had clicked the hour and turned a small hourglass held in golden filagree. "Oh, look at this one, Sev!"
"I suppose it is as feminine as you'll find, Lily." Severus remarked, not rising to the bait. Avery and his gang had stopped bothering him long ago, whereas Potter was eternally a thorn in his side. Still, he studied the girl in suspicion. There was something off about her, as though the earth had moved and not come back together properly, all jagged edges. He couldn't say what, as she chatted with Lily and wrapped up the watch, but there was something off about her. He scowled slightly, unwilling to push it for fear of Lily telling him that he needed to be friendlier, and fell into silence. Still, he couldn't help a parting question as he followed the redhead out of the shop toward Florean Fortescue's. "Where did you live in Greece, Persephone?"
The girl's face changed, shifting from a smile to a forlorn, lost look Severus had seen on Eileen Snape's face more than once. A look that suggested bone-deep loss, as if she could never go home again. "Hermione." She said softly, and he almost felt guilty for asking. He nodded slowly, and left.