Ok, this is kind of a frequently asked question; I know Astoria was a couple years younger than Harry in cannon. Just go with it.
"Fastest broom in the world-better than the bloody Firebolt!" Harry grinned at the throng of boys gathered around the quidditch store, eyeing the Firebolt 2000, the latest racing broom as of last month. The boy who had spoken was rather tall with curly blonde hair and big gaping brown eyes hidden under large square spectacles, and as he turned to his friend to list the brooms superior attributes to all previous models Harry was strongly reminded of Ron.
He took a sip of his coffee, which he'd picked up at the leaky caldron on the way into the Alley, even though he was nearly twenty years old, and could apparate (with several months of coaching from Hermione) perfectly well, Harry could never shrug the habit of entering through muggle London. He'd come to Diagon Alley on the pretense of picking up a fresh bag of owl treats for Louis, the rather scruffy owl he'd purchased last year after Hermione had refused to let him borrow Demeter-who at the point was practically living at his house. He had begrudgingly agreed, and disgruntled fumbling Louis had his own charm that reminded Harry strongly of Neville Longbottom, but he doubted they would ever grow as close as he had to hedwig.
Honestly, owl treats were on the back of his mind. A week had passed since he'd met with Astoria, and in that time he'd managed to convince Ron and Ginny to meet with there Slytherin counterparts (though Hermione remained stubbornly marooned in her room). As far as he could tell from the bits of Ron's emotional (and very loud) rant, his best mates meeting with Parkinson had gone over with a lot of arguing and shouting, knowing the two of them it probably would have been worthy of Rita Skeeter's gossip column. The details were a bit foggy, as Ron's words had been difficult to discern, but whatever they had said had escalated enough to get them kicked out of the Hog's Head, a pub well publicised for it's admittance of rather shady customers. Ginny had returned a mere 30 minutes after leaving, wand in hand, muttering something about a tricky hex and scummy pureblood activists. He hadn't seen her since, but it had only been a few hours ago that she'd disappeared, so he wasn't worried. Ginny could take care of her self.
Still, Harry's life had gone of the deep end a bit in the last couple days, and he would've used nearly any excuse to escape the confines of the burrow. Even Grimmauld place had become unbearable as his friends had taken to flooing over in turn to talk (very loudly) about whatever was bothering them, and digging into his reserves of tea faster than Kreacher could replenish them.
People watching on Diagon Alley seemed the easiest escape. The well known little street had been quiet in the years after the war, the shops still plastered with wanted posters and purple flyers, even a few "undesirable no. 1" pictures had survived. About six months ago, after dealing with Hogwarts and Hogsmeade, and most prevalently the ministry, Kinsley had arranged a task force to rebuild the Alley. It was nowhere near as crowded as it had been nine years ago when Hagrid had taken him to buy his first year school things, but as a plump which in emerald green robes teetered by his bench muttering about the price of dragons hide Harry couldn't help but smile.
He'd stopped by Eeylops Owl Emporium to pick up the treats (he really did need some), and flourish and blotts, to sell a large stack of Lockhart's books he'd found in his school trunk. Getting it from the Dursleys had been awkward to say the least, as he hadn't expected to see them again after his seventeenth birthday-but to his surprise his little bedroom was untouched, and the small family had been terse but not rude as he visited them one last time.
Harry wiped a sleeve across his forehead, glancing across the street. his In the heat of the day Florian Fortescue's little ice cream stand, it's colorful banner still waving proudly after all this time, was very tempting, and Harry decided to risk the trek across the road for a cone chocolate and raspberry with extra nuts.
He was in cognito, which felt terribly stupid, but he really wasn't in the mood for a mob of crazed followers asking him to sign their napkins. Honestly a baseball cap (to cover his tell-tale hair) and a pair of contacts, which he loathed, were usually enough to disguise him. But he'd also strapped on a pair of ray-ban, because it was crowded and if anyone recognized his green eyes...Harry shuddered.
Somehow, he managed to make it to the shop without incident. Harry strode up to the booth, the line had cleared, attempting to be casual and glanced into the window.
"Hullo," Florean Fortescue said brightly, sliding a menu across the service window. "What can I get for you today?" Harry pushed his sunglasses further up his nose.
"Chocolate and Raspberry, extra nuts," He said, smiling at the smells wafting from the little cart. "Please," he added quickly, starting out of his trance as the little man turned to go. Florean Fortescue, instead of going on with scooping out the ice cream, made an abrupt about face, staring at Harry in a very peculiar way before breaking out into a grin.
"Little Harry Potter," He said, his smiling growing wider. Harry cursed under his breath. "I'm sure it's you young man! I remember when you were only thirteen years old, coming over here to finish your history homework-"
"Yes, yes alright," Harry said pulling his hat farther over his forehead so the brim shadowed his face and doing a quick sweep of the idle shop to check that no one had heard the vendor. When he was sure he hadn't been spotted he looked back at Florean who was staring at him in a rather disgruntled way, like he hadn't been ironed after a go through the wash.
"I suppose you get a lot of people noticing you on the streets I didn't mean to be-"
"No no," Harry said, trying not to sound too frustrated. "It's not that at all, I just-" he winced slightly. "I'm in disguise Florean-I don't want anyone mobbing me."
"Oh," the ice cream man grinned. "That's alright then," he said, running a finger over his lips. "Mums the word." Florean swiveled around to fetch the nuts as Harry glanced around the shop once more to check for crazed fan's-all of which made him feel very self-centered and awkward.
And then he spotted her, leaning against one of the candy striped umbrellas that shaded the ice cream stands little red tables, her blonde hair was braided haphazardly over the shoulder of a white t-shirt with the british flag plastered over it's front. He grinned and nearly called out-but then remembered that she might not recognize him, they'd only really met once. He grabbed his cone from Florean muttering a quick thank you and handing him a few sickles, and then rushed over to Astoria who was seated now, peering into a small blue leather book. He was about as close as he could get now without touching her, and so figuring it would be simplest he tapped the blonde on the shoulder.
"PETRIFICUS TOTALUS!" Harry barely had time to squeeze out a "Bloody Hell!" Before his body went rigid, and he toppled backward, his sunglasses slipping off his nose, his wild hair slipping out his hat. His ice cream falling tragically to the cobblestones.
"Oh my god!" Astoria squealed, kneeling down towards his head and waving her hands awkwardly around her face. "Harry I didn't-Oh Merlin!" Harry tried to shake his head, but the body bind kept him still. Please no one notice me, please!
"Erm," Astoria said, glancing quickly back and forth. "I don't-" She leaned in towards his chest as if to check his breathing. "Thank merlins saggy left buttcheek you're alive!" She looked at him in a relieved way that warranted response-but the spell, which was impressively strong-restrained him.
"I mean I don't know what I would've done if I'd killed Harry bloody Potter-I think all of Britain would come rioting at my doorstep. I'd have to go live amongst the woodland people." She smirked as if this was some sort of odd inside joke he had no precedent on which to understand. Harry, though very keen on talking with her would rather like it if she would perform the counter curse-as people were starting to stare at his stiff body, and Astoria was still kneeling very close...
"Oh!" She said suddenly, interrupting her own rambling speech. "Finite Incantatem." Harry blinked and stretched his arms, once again limber-scrambling rather stiffly to his feet and tugging his hat back over his hair.
"Merlin's saggy left buttcheek?" Harry said, grinning as he popped the sunglasses up with the toe of his trainers. Astoria blushed deeply and punched his shoulder good naturedly. He tried not to wince, her bony knuckles reminded him unpleasantly of aunt Petunia.
"I thought you had died!" Harry grinned and placed a hand over his heart.
"I didn't know how much you cared." She grumbled something about scar headed idiots and then sighed, glancing at his waffle cone which had shattered on impact.
"I don't think I can save that-my 'repario' has always been a bit rusty." She glanced over at the little white metal table-cut out in a pattern that reminded him of the paper snowflakes he'd made in primary school. Resting in it's center was a glittering crystal bowl piled high with-he grinned-chocolate and raspberry, extra nuts. "I have plenty," Astoria finished, as though reading his thoughts. He grinned plopped down in one of the little white chairs, and Astoria did the same, her pale features striped with the red light that filtered through the worn umbrella.
"What?" She asked frowning, and Harry realized he'd been smiling.
"You look like a human candy cane," he said matter-of-factly grabbing the little silver spoon ducked under the cherry that topped off her Sunday. "And I'm going to eat all of your ice cream." She laughed, then pointed over in the direction of Flourish and Blotts. "Isn't that Weasley kissing Pansy!"
Harry was so startled he dropped the spoon, which he'd positioned just above a great cluster of nuts, nearly toppling his chair as he swiveled in his chair. "Where?" He said turning squinting through his contacts as he turned back to Astoria who was taking a heaping bite of ice cream.
"Gryffindors," she said, grinning as she twirled her spoon through the dessert which was just out of Harry's reach. "So gullible."
"You sneaky bastard!" He said grabbing for the bowl which she pushed away with her pinky finger.
"I thought we were past petty insults Harry," she said with a dramatised sigh."
"Restricting ice cream crosses the line," Harry said grinning as he slipped his wand from under his sleeve. "Expelliarmus!" The bowl, and the spoon which was dangling from the Slytherins left hand soared towards his ready hands and he grinned at her surprised expression. Before she could do anything else he balanced a great scoop of chocolate on the teaspoon and shoved it into his mouth, bits of ice cream dripping down his chin. She laughed as she wincing at the state of his face.
"That's disgusting-you realize the human mouth is not meant for that quantity of ice cream." Harry took on a solemn expression and mimicked the voice Dumbledore had always done before telling him something unspeakably wise that he would only appreciate a few months later.
"Alas, I adhere to no such restrictions." She laughed again.
"Well you look like a dunderhead." Harry grinned, an idea forming in his head.
"Here," he said, grabbing a napkin from the plastic dispenser. "You've got something on your nose." He reached over, and just as his had reached her face he stuffed his hand into the soupy ice cream and wiped it across her cheek. Astoria's jaw dropped and then she frowned.
"Oh I see-a rematch." Harry flinched at the reminder of the tickling battle they'd had only last week-which was his fatal mistake. He felt the cold stuff slosh over his forehead and quickly wiped his napkin over his exposed eyes, tossing a gob of sundae blindly towards the blonde. A squeal told him he'd met his mark, and soon the two of them were catapulting ice cream across the sticky table, laughing and screaming in Astoria's case.
"OY!" Harry blinked through a great chunk of frozen raspberry and spotted Florean Fortescue, a bit of chocolate dribbling through his wispy silver beard. Astoria, who was drenched in pink covered her mouth and Harry couldn't help grinning.
"Sorry Florean," He said catching Astoria's eye and sliding out of his chair. "We were just-er-leaving." The blonde Slytherin turned to follow him, digging a pale hand into her pocket and handing the angry vendor a green velvet pouch.
"Thank you for the ice cream," she said, obviously trying to keep a straight face as she turned and followed him towards the leaky caldron. Harry was very tempted to look back, if only ot see the expression on Florean Fortescue's face, but walked quickly to the shabby little coffee shop trying not to laugh-as he could practically feel the old man's eyes burning through his back.
"Oh god!" Astoria said when they were out of earshot, laughing as she met his eyes. "You look so awful! And not just because of that ridiculous hat!"
"I'm in disguise!" He said defensively, blushing a slight pink.
"Really?" Astoria asked widening her eyes. "Is there another world terrorist you're prophesied to overcome? Because I'll admit, that's a bit of a deal breaker."
"Well," he said smiling. "Do you want a list-or is this more of a prophecy to prophesy basis, because those are two entirely different sets of paperwork." She shoved him playfully and laughed.
"You really are a mess though Potter-er Harry." She reddened and her mistake and Harry laughed, feeling that pleasant kind of awkwardness that always accompanied a new friendship.
"Well I've got to go back to Grimmauld place-Kreacher might call the aurors last time-and I've been a witness in that bloody trial room more than times than I can count," he glanced up at Astoria, making a split second decision. "But you can come by for lunch if you want."
The Slytherin girl looked startled, but then she grinned. "Yeah, that sounds brilliant."
Basically fluff. But new chapter is coming like BACK TO BACK early. Hope you enjoyed and please review!