Y/N was getting more interactive and fonder to Malfoy which Harry and the others couldn't help but notice it. Malfoy did not mind having her as company and would even let her stay for a normal chat, which came to them as a great shock.

Draco had always seemed impossible to be friends with to the Trio, as they were like oil and water; they could never get along.

But somehow, Y/N managed to get close and effortlessly befriended him, leaving the Trio conflicted. Why would their friend be hanging out with their mortal enemy? What exactly was she playing? The three of them felt frustrated as if Y/N had betrayed them.

"Y/N," Harry grabbed her by the arm with a serious look with Ron and Hermione lingering behind him. "We need to talk."

"Sure, Harry, what is it?" Y/N innocently asked.

"Why are you friends with Malfoy?" Ron spoke up, looking slightly betrayed. "You know he's bad—"

"He's not all that bad once you get to know him."

"Not that bad?" Ron scoffed in disbelief. "He called Hermione a Mudblood, he makes fun of us all the time, he never treats anyone with decency– HE'S ROTTEN TO THE CORE!"

Y/N winced, understanding their frustration. If she hadn't known better, she probably hated him too. But Draco could change, even if he didn't know it yet.

"I know... what he did was bad and there's no excuse for his behavior. But we should give him a chance–"

"Right, give Malfoy a chance to change," Ron shook his head, disapprovingly. "Like when hell freezes over; it's never going to happen."

However, Harry and Hermione seemed more contemplative about Y/N being friends with Malfoy. They were still against the idea of giving him a chance but they saw something useful in it.

"No, wait—" Hermione interrupted with a calculative expression. "Maybe it's a good thing you have won his favor, now you can ask him what he knows about the Chamber of Secrets."

"Along with other things that we might not know what he's planning to do. You could give us a heads up." Harry said, thinking the same as Hermione.

"So... You want me to be your spy?" Y/N asked slowly for confirmation.

"Yes!"

Y/N felt uncomfortable with the idea. She was friends with Draco for a genuine connection and not to fish out information from him. Faking a friendship for the sake of spying on them just felt so wrong to her.

But Y/N knew that if she refused them, they'd find her suspicious and might even think she was protecting and siding with Malfoy. She didn't want that either. Left with no choice, she sighed in defeat and reluctantly agreed to their plan.

*

Christmas was around the corner and with several students petrified by an unknown cause, the Hogwarts Express was stampeded with students, all wanting to get as far away from Hogwarts on the Christmas Holiday. Scared that they might be the next victim.

So, around Christmas, Hogwarts was almost empty. The only students left were the Golden Quartet, the Weasley siblings, Draco Malfoy, Crabbe, Goyle, and a few others.

Since only Y/N's friends and the Weasleys were staying in the Gryffindor dormitory, she had no problem entering their common room whenever she pleased, as they welcomed her with open arms.

Fred and George excitedly showed her some firecrackers that they had smuggled from home. They set a small one in their common room, which made a loud explosion.

Since there were barely any students left at Hogwarts, they could make all the noises they wanted without bothering anyone. Everyone seemed to be having fun except for Percy Weasley who thought they were being childish.

Y/N joined with Fred and George's shenanigans and helped them secretly place small harmless explosives under random students' beds so that when they returned from their holidays, a surprise would be waiting for them.

However, Percy confiscated all the firecrackers, saying it would cause too much trouble for the Gryffindor.

Disappointed, Fred and George left ten of them under Percy's bed instead. Not the dangerous kind but certainly frighteningly loud. That ought to quench their mischievous desire after seeing Percy's shocked reaction, at least.

*

Y/N had eaten so much food on the night of Christmas dinner that she could just burst! She had barely finished her fourth helping of Christmas puddings when Hermione had ushered her, Harry, and Ron out of the Great Hall to finalize their plans for the evening.

They discussed for a bit before Harry and Ron reluctantly agreed to impersonate Crabbe and Goyle. Hermione set up a trap for those two blockheads and tricked them into eating chocolate cupcakes with a hint of Sleeping Draught. 

After they fell unconscious, Harry and Ron quickly took their clothes and a sample of their hair before heading to Moaning Myrtle's bathroom where they were met with Hermione and Y/N.

"Did you get it?" Hermione asked breathlessly.

Harry showed her Goyle's hair.

"Good."

The four of them stared into the cauldron. Close up, the Potion looked like thick, dark mud, bubbling sluggishly.

"Yuck," Y/N shivered in disgust. "I can't believe you guys are drinking that."

The three of them gulped, and couldn't believe it either that they were about to consume such a disgusting thing.

"What now?" Ron whispered.

"We separate it into three glasses and add the hairs."

Y/N was initially going to join them in drinking the Potion, she was going to impersonate Pansy Parkinson. However, that was before she and Draco became friends.

Now, it seemed unnecessary as she could just talk to Draco normally as herself. But of course, that was not the case for the Trio which is why they had to take the Polyjuice Potion.

Hermione's hand trembled as she added Millicent Bulstrode's hair into her glass of Polyjuice Potion. The Potion hissed loudly like a boiling kettle and frothed madly. A second later, it had turned a sick sort of yellow.

"Urgh— essence of Millicent Bulstrode," said Ron, eyeing it with loathing. "Bet it tastes disgusting."

"Add yours then," said Hermione.

The boys added theirs in, too. Both glasses hissed and frothed.

"Ready?" Hermione looked at Harry and Ron anxiously while holding up her glass.

"Wait, Hermione— " Y/N stopped her, "Are you sure you want to do this?" Knowing that wasn't Bulstrode's hair she added.

"No, I'm not so sure anymore..." Hermione gulped. "But the plan must go on. It has to be tonight or who knows what Malfoy will do next if we didn't stop him."

Hermione took a brave inhale, and before Y/N could have the chance to say anything else, Hermione quickly forced herself to drink the Potion. Seeing her bravely drink the muddy thing, Ron and Harry followed right after her.

They took two sips, Ron looked mortified. "I think I'm going to be sick–" He dropped his glass and dashed into one of the cubicles.

"Me too–" Hermione let go of her glass and sprinted toward the cubicle next to Ron with a bang.

After an excruciating moment of transformation, the boy who once looked like Harry Potter had turned into the image of the thick Gregory Goyle. He breathed heavily, still panting from the painful transformation as he collected himself.

"Are you alright there, Harry?" Y/N quietly asked.

"Yeah, I'm fine..." Goyle's low rasp of voice issued from his mouth.

Ron's door opened. They stared at each other for a moment.

"This is unbelievable," said Ron, approaching the mirror and prodding Crabbe's face. "Unbelievable."

"We better get going," said Harry. "We've still got to find out where the Slytherin common room is."

"Don't worry, I sorta know where it is," Y/N said.

"Great," Harry looked relieved.

Ron banged on Hermione's door. "C'mon, we need to go."

A high-pitched voice answered him. "I– I don't think I'm going to come after all. You go on without me."

"Hermione, we know Millicent Bulstrode's ugly, no one's going to know it's you."

"No– really– I don't think I'll come. Just go, you're wasting time."

Harry was about to ask Hermione some more when Y/N tugged on his sleeve, shaking her head and telling him with her eyes that they should just leave her alone. 

Harry checked at his watch. They had exactly one hour before they transformed back to their original appearances. Five of their precious sixty minutes had already passed.

"We'll meet you back here, alright?" he said.

The three carefully left the girls' bathroom without Hermione as they navigated through the halls and the hundred corridors, following Y/N's lead and making their way down to the dungeons.

Harry and Ron had no idea where the Slytherin's house entrance was but the truth was, neither did Y/N.

She had never been inside it, let alone knew the exact location. All she knew from playing various Harry Potter games was that they shared one thing in common: it was in the dungeon and had a serpent statue near its entrance.

But that's not nearly enough, is it?

"Uh, Y/N?"

"What?"

"Are you sure you know the way to the Slytherin common room?"

"Why'd you ask?"

"Because it appeared we're going in circles... And you don't look as confident as you claimed."

Y/N didn't realize how obvious she had been. She kept looking left and right, scanning everything whilst trying to remember any details she could remember from the games, books, and movies that might indicate it was the Slytherin common room. Alas, it was proven in vain.

Suddenly, a figure appeared from the opposite direction, nearing the three of them. To Ron's surprise, it was his brother, Percy.

"What are you doing here?" said Ron, forgetting he looked like Crabbe.

Percy looked affronted. "That," he said stiffly, "is none of your business. It's Crabbe, isn't it?"

"Wh– oh, yeah," said Ron.

"And you," Percy looked straight at Y/N. "What are you doing down here in the dungeon with these blokes?" He eyed her suspiciously.

"They're my friends," Y/N said quickly but Percy looked unconvinced. "Seriously, Percy, Ron isn't my only friend, you know."

"Crabbe, Goyle—" A sharp voice suddenly pierced behind Harry, Ron, and Y/N. It was Draco Malfoy as he strolled towards them. 

"There you are," he spoke, looking at them. "Have you two been pigging out in the Great Hall all this time? I've been looking for you–"

Draco only realized Y/N was with them until he got much closer. "Oh, hey, Y/N." He drawled.

"Hey, Dray," she said smoothly.

Draco turned to Goyle with glasses and eyed him suspiciously. "Why are you wearing glasses?"

"Um, reading–"

Harry panicked a bit. He had completely forgotten to take off his glasses after transforming to Goyle so he quickly did so.

"Reading?" Draco frowned deeply, slightly surprised by the new discovery. "I didn't know you could read."

"Yeah, Goyle don't usually read..." Y/N whispered to Harry.

Malfoy glanced witheringly at Percy. "And what're you doing down here, Weasley?" He sneered.

Percy looked outraged. "You want to show a bit more respect to a school Prefect! I don't like your attitude!"

Malfoy sneered and motioned for Harry, Ron, and Y/N to follow him. Y/N flashed Percy an apologetic look, and Harry almost uttered the word 'sorry' but caught himself just in time.

Once they were away from Percy Weasley, Draco finally spoke again. "So, what are you doing down here, Y/N? And with Crabbe and Goyle as well?" He lazily asked.

Y/N shrugged nonchalantly, "I was wondering if I could come inside your common room and hang out."

Draco stopped in front of a wall and turned to look at her confusedly. "You want to come inside our common room and hang out?" He repeated.

She nodded eagerly.

Draco eyed her clothes up and down before saying bluntly, "Sorry, no Ravenclaws allowed."

"Oh, come on," she playfully exasperated. "I'll let you in Ravenclaw's common room~" She suggested temptingly.

Draco quickly looked at her, intrigued. "You could do that?"

"Of course, I can and I'll do it just for you~"

Draco smirked, liking their negotiation, "And what if we get caught?"

Y/N returned with a devious smirk, "Well, we'll just have to be discreet about it and not get caught." Her Slytherin side was showing.

Draco chuckled, liking the idea of sneaking inside Ravenclaw's common room very much while Harry and Ron looked at them bizarrely. So this is how Y/N acted around Malfoy, they thought.

"Deal," Draco said firmly before turning to the wall. "What was the new password again?" He asked Goyle.

"Uhhh..." Harry struggled.

"Lemme guess," Y/N looked at Draco knowingly. "Pure-blood?"

To which Draco burst out laughing, he found it ironic. "You're actually right. Pure-blood!"

And the flat wall in front of them revealed itself and the door to the Slytherin common room was accessible to them.

"Come on," Draco nodded and the three of them followed him inside.