It was all Ron's idea. Harry had to admit to himself that, yes, it was a funny prank, even if it was borderline malicious. It started out as a passing fancy of Ron's, which he had voiced aloud one evening as he and Harry played chess in the common room. They had been waiting for Hermione to return from the library, where she was searching for information on Flamel. She had just returned yesterday from her parent's house, right in time for the term to start the next day. Neither Harry nor Ron had yet had the chance to tell Hermione of Harry's discovery, as she insisted on throwing herself into heavy research mode on the first day back.
"Hey, Harry, I wonder what Hermione would see in the Mirror?" Ron had asked, his knight smacking one of Harry's poor pawns in the head, knocking him off the board with the blunt side of his broadsword.
"Mmm. Probably something to do with books," replied Harry absentmindedly, as he sought for a way to maneuver his bishop to take out one of Ron's white rooks.
"We should take her to it and see what she says!" Ron suggested gleefully, his tone conspiratorial.
Perhaps it could be blamed on the cozy environment of the Gryffindor common room, with its warm reds and golds, and the crackling magical fireplace emanating a comforting heat all around them. Or maybe Harry could just justify it with those Chocolate Frogs he'd eaten earlier that day that tasted funny, but he had jokingly agreed with Ron that they should take Hermione to see the Mirror.
Until Ron had seen it for himself, he was dead-set against Harry returning to visit his deceased parents for the third night in a row. Harry had told him about how he'd come upon Dumbledore in the unused classroom, who proceeded to inform him of what the Mirror truly showed. Dumbledore had asked him never to go looking for it in the castle again, as it was to be moved once the holidays were over. He warned that the Mirror could be a dangerous thing to unhappy people. So it was a bit surprising to Harry that Ron would want to visit the Mirror one last time, with Hermione, before it was relocated.
Ron's spin on the idea was to take her to the Mirror and ask her what she saw, explaining that the Mirror had the power to see the future. They would tell Hermione that they couldn't get it to work right, and could she pleasepleasepleasehelpthemfigureitout?
Despite her initial usual protestations against rule-breaking, Ron knew that both Hermione's curiosity and inherent need to show off her brains would persuade her to come. After Hermione returned from the library, they managed to convince her to accompany them. The three waited for everyone else to go to bed, then snuck out into the darkened corridors under Harry's cloak.
"Come on, Hermione, it's really amazing," Ron insisted, ushering the bushy haired girl ahead of him. Harry lead the way down the corridor and towards the library, where he planned to look for the now familiar suit of armor located by the room that housed the Mirror.
"Ron, if this is just one of your hair-brained schemes to get me to tell you the answers to next week's Charms exam - " Hermione began whispering sharply, when Harry suddenly stopped in front of her, causing her to bump into him, and Ron to crash into her, almost knocking all three of them over.
"Shhh!" Harry hissed, standing completely still and listening carefully. Hermione and Ron behind him froze as well, holding their breath.
Down the corridor, the three students could hear the malicious cackling of Peeves the poltergeist as he no doubt broke something that didn't belong to him.
Harry grabbed Hermione's arm, who in turn grabbed Ron's, and lead the three of them down a corridor to the left, towards the library and away from Peeves and his penchant for spotting them at the most inopportune moments.
After a few tense minutes of silence, they passed the library and both Harry and Ron attempted to remember the route to the unused classroom while avoiding anyone who might be patrolling after hours. Harry first spotted the suit of armor, and using it as a reference point, they finally reached the room that contained the daunting Mirror of Erised - unknown to Hermione, of course.
Harry crept into the room, passing the neglected desks and chairs piled against the walls. He stopped before he reached the Mirror, standing outside of its field of view.
Pulling the cloak off himself and his two friends, Harry motioned to the Mirror. "Here we are," he told Hermione, sending Ron a scolding look when he saw that the redhead could barely contain his glee.
Ron quickly walked around the other two and stood directly in front of the Mirror. Harry could tell by his expression that Ron was still in awe of the image it reflected.
Hermione stayed standing beside Harry, observing the Mirror from a distance.
"That's a strange looking language..." she murmured, trying to decipher the inscription on the top of the tall golden frame that reached the ceiling.
Erised stra ehru oyt ube cafru oyt on wohsi.
"Well it's obviously important, if someone hid it in a room like this," stated Hermione. "W-what do you see?" she asked Ron hesitantly, as he was still marveling in front of the Mirror.
Seeming to catch himself, with visible effort, he looked away from his heart's desire, and addressed Hermione, a melancholy glaze in his eyes. "I see... myself, holding next week's Charms exam, but I can't see what I got on it..." Ron lied, looking guilty for the first time since he'd hatched his plot.
"Maybe it's a sign that you should study for it," joked Harry, trying to lighten the mood. Hermione turned to him, curious.
"What do you see in the Mirror, Harry?" she asked, not noticing Ron frantically shaking his head at Harry from behind her.
"I... don't see anything. That's why we need your help. I can't get it to work for me," Harry replied after a second's hesitation, feeling a knot form in the pit of his stomach at the fabrication. Ron nodded at him from behind Hermione, grinning.
"Hmm." Hermione turned around to examine the Mirror, and Ron immediately straightened up and tried not to look excited.
"Go try it out! See what you... see..." Ron suggested, gently pulling Hermione towards the Mirror as he pivoted himself around her to stand beside Harry.
As Hermione slowly approached the Mirror, Harry began to truly regret their decision to go through with acting on Ron's whim; he thought about how he would feel if someone had manipulated him into viewing his parents' smiling faces, knowing that it was a false reality, and taking pleasure in that knowledge.
He was just about to reach out and grab her; lead them all away from this hopeless room and the unbearably cruel Mirror it contained, but Hermione did something that surprised him.
She laughed.
Ron raised his eyebrows and looked at Harry sideways.
"Odd," was all Hermione said, in a bemused voice. She looked over at them, then at the Mirror again, before scoffing.
"Well...?" urged Ron, taking a step towards her.
"It must be broken or something," Hermione answered, shrugging.
"What do you see?" Harry asked quietly, unmoving and making an effort to not look at even the frame of the Mirror.
It would be years until Harry and Ron could truly comprehend all the meaning of what Hermione saw in the Mirror of Erised that night.
"Us."
Ron started. "You and Harry!" he exclaimed, incredulous.
Hermione turned and looked at him like he was crazy. "All of us. The three of us."
Ron pulled back; his posture reminded Harry of a deflating balloon.
"How do you mean?" Harry asked seriously.
"We're grinning like idiots... it's a bit creepy," replied Hermione offhand, amused by the reflection she saw in the Mirror.
"So it's just us three? What do we look like?" Ron questioned, quickly looking over at Harry in confusion.
"Like we do right now," Hermione said. "Perhaps something good is going to happen soon?" she pondered, stepping closer to the Mirror.
"I doubt it," Harry muttered so low that the others couldn't hear.
"We look exactly like we do right now?" pressed Ron, a tinge of disappointment piercing his voice.
"Yes, Ron! We - " When Hermione was so close that she almost had her nose against the glass, she stopped speaking abruptly.
"Whoa... wait..." she whispered, a look of shock dawning on her face.
"What is it?" asked Ron eagerly.
"What is this thing?" Hermione suddenly asked, her voice bordering on alarm.
"What do you see?" Harry asked again, unable to dismiss the haunted look in Hermione's eyes.
"It - you... there's no way this Mirror shows the future," Hermione stated solemnly.
"Why not?" Harry asked, holding his breath.
Hermione took one last lingering look at the reflection of her heart's desire in the Mirror, before turning to Harry with tears in her eyes.
"Because you don't have your scar."