"Don't you people have stories anymore about wishes?" The reflection-Jake asked with a wicked smile. "There's always rules and there's always consequences. You can't undo the cost of a wish with your own wish, but someone else can, and I've been wishing really hard to get out of here. Problem is, I got stuck here because I made a stupid wish, and I can't grant my own wishes."
Jake was backing up from the mirror, not liking where this was going, but he wasn't used to his bigger feet and longer legs and ended up stumbling over himself, falling to his bare ass on the wooden floor. The reflection-Jake snapped his fingers and Jake felt a pulling sensation, like something was being ripped out of him. His vision fuzzed and after a moment he was looking at his new naked adult body sitting on the floor of the attic through the mirror, except he was standing now.
"Two hundred years I've been stuck in there." Reflection-Jake said as he stood up, rolling his shoulders and looking down at himself with a grin. "At least you wished me up a nice body first. Would have given you a bigger tool if I knew you were going to let me out this quick." He gave his manhood a bit of s wiggle with his hand, then he bent over a picked at the shredded clothing at his feet, and pulled up a shirt that was perfectly fine, tugging it on. Jake felt a the same shirt appearing on him.
"How'd you do that?!" Jake stammered and his reflection looked at him with an arched brow. "Part of your wish. I had to tweak reality to make you older, your mother is your older sister now, or my older sister, rather. It takes reality a bit to catch up, so some things change on a bit of a delay, like your possessions." He reached down and picked up a pair of jeans, grinning. "Neat, huh? You'll figure this all out over time, I'm sure."
Jake looked around him, he could see part of the attic. It was the exact part that could be seen from the mirror, beyond that was just a grey fog. "How long are you going to leave me here?" Jeans appeared on Jake's legs as reflection-Jake tugged on his pants in the real world.
"Me? If I make a wish it'll be carefully worded, trust me. You're just going to have to wait until someone else wishes you out." Reflection-Jake ran a hand through his hair, grinning at his reflection in the mirror. "Only way out of there is if some poor sap wishes you out, then they have to replace you. Someone has to be in there. Now it's you." He walked over to one of the boxes and plucked out the photo album he had originally come up here for. "Now if you excuse me, I'm going to go give this to my sister and mother so they stop bothering me, then maybe go out on the town and see if I can get laid. It's been so fucking long."
As his old body headed to the ladder down, Jake felt his form fuzzing. Once it was out of sight he lost his body and puffed into mist. He was still aware, floating. But it also felt like he was half-asleep, drifting. He didn't know how long he floated in that semi-void. Time just didn't seem to make sense anymore, maybe it was some precaution to keep him from going insane and losing his mind during long bouts of tedium. New thoughts entered his mind. How to grant wishes, how strong a cost was appropriate for which wish, all the little rules and nuances his reflection had known but he hadn't. In his dream state he learned how to be the mirror.
Then he felt himself pulling back together. With a rush he felt everything returning to him along with the new knowledge. He snapped together into a new body, a reflection of the person standing in front of the mirror...