When prankster meets bookworm

Pinkie swear

A/N

This chapter is set during fifth year and is a oneshot on it's own.

"What do you think you're doing?" Her stern voice startled both twins and they almost dropped the bottle they had been hiding all day.

"Nothing to break your pretty head about, Mione." Fred said, as both him and George turned around, their hands behind their backs.

"So, when Ron gets back in here and wants the 'refreshing' drink your mom 'made' for him, he's not suddenly gonna sprout... I don't know, pink hair, a pigtail, or anything remarkable funny?" She had her hands put on her hips and gave both of them a raised brow.

"We're hurt." George said, bringing one of his hand towards his heart.

"Why would you think we would ever do that to our dearest brother?!" Fred asked, his hands staying perfectly out of her sight.

"Because, Freddy dear." Hermione said, walking closer to the twins. "You haven't shown me your hands yet." She had whispered the last part in his ear, reaching with her hand behind him and grabbing the bottle he had been hiding for her before he could do anything.

"Smooth Mione." George chuckled. "But could you please hand us the bottle back. We weren't done with that yet."

"And why would I do that?" The girl said, sitting down on the chair next to Fred, one of her legs over the other, giving the boys an amused look.

"Because you are as pissed at our dearest brother as we are." Fred said smugly.

"Otherwise you would have called mom in already." George added.

"Well, you can get it if you explain to me what you've put in it and how you made it." She said, giving both boys a wink.

"Always so demanding." Fred chuckled.

"Well, come on then, Miss I wanna know it all." George said, tapping Hermione's knee.

"Let's discuss this somewhere in private." Fred gave her his hand and helped her up, before leading her up to their room.

Grimmauld's Place felt more and more like a place you actually could live and when Hermione entered the twins their room, she could see the potential the house had. It almost felt like in the burrow again, the room all messy and comfy.

"Take a seat." Fred said, motioning towards the beds before opening a drawer and looking through it.

Hermione looked around and sat down on the end of one of the beds, a little bit nervous. This was the first time she was in their room and she was all alone... But her curiosity was bigger than her nervousness so she waited patiently. George jumped on the other bed and laid himself down, his hands behind his head and a large grin plastered on his face.

"So, since when do you want to know what we are doing, Mione?" He asked, his head turning in her direction, curiosity clearly visible in his eyes.

"What the two of you are doing, is some extraordinary magic. Why would I pass by a chance to learn?" She explained herself.

"Well, if that's why you're here, you're on the right place." Fred said, sitting down next to her. "Here." He handed her a little, red book. "Now, I can't let you take it out of this room, we wouldn't want our secrets to get out, but you can take a look at it now, if you swear to never speak a word about it."

"I swear." She said, reaching out with her hand, her pinkie outstretched.

"What – what are you doing?" Fred asked confused, looking at her hand.

"I want to pinkie swear on it." Hermione said, retreating her hand self-conscious and looking down at the ground. What had she done wrong?

"What is a pinkie swear?" Fred asked, gently putting his fingers under her chin to make her look up again at him.

"It's the muggle version of an unbreakable vow." Hermione muttered.

"Muggles have unbreakable vows too?" George piped in, sitting up and giving the girl a surprised look. "Now that's interesting. What happens if you break the vow?"

"Well..." Hermione hesitated for a moment. "It comes from the middle ages and when you broke it back then, well it costed you your pinkie." She wasn't surprised both twins seemed extremely excited when they heard that. "But, now... I don't know anyone who ever broke one and it means the end of a friendship in my eyes."

"If you say it means that much to you, I'm gonna trust you on it." He offered her his pinkie and she took it with a smile.

"So, can I read it now?" She asked with a shy smile.

"That's why I gave it." Fred chuckled.

He walked over to George's bed and kept an eye on the petite brunette. Sometimes he wondered why she didn't end up in Ravenclaw. He studied her features; the little frown she got when she thought about something interesting, the little smile she got when she appreciated what she read or the twinkle in her eyes whenever she picked up a good book. All of these features were present right now and he started smiling himself. He didn't notice that his twin was observing him like he was observing Hermione. George knew his brother better than anyone and it was obviously that he had a thing for the brunette. The fact that he just had given her their most valuable property proved it just once again.

"What is this?" Hermione asked, pointing at something in the little book.

"Oh, that's just an idea in working." Fred answered, taking a look at the page she had opened. "We are planning on making a portable swamp but haven't figured out yet how to carry something so large in something this small." He showed her how big they were planning on making it and Hermione frowned.

"Well, you could always try the Undetectable Extension Charm." Hermione said, shrugging her shoulders.

"That's a brilliant idea." Both twins agreed.

"Something so simple and we didn't think of it." George complained.

"We can't all be geniuses like me." Hermione joked before turning the page. But she didn't get a chance to read it, seeing that screams from downstairs caught their attention.

"I have a feeling Ron couldn't wait to enjoy his drink." George said with a small smirk.

"Let's go and enjoy the view." Fred added, helping Hermione up from his bed who put the little book down with a smile.

"I'm curious how this turned out." She said with a smile. "And just so you know, I'll b" your alibi." She winked at the twins before walking away, swaying her hips.

"Let's keep her around, Gred."

"She could indeed end up being useful, Forge." George grinned.

"And good companion too."