"Narumi! Where did you go?"

Ruri called out several times to her rabbit-fied friend, but had no reponse, as Narumi had spared no time in rushing down the spiral of corridors that confronted them. Looking on each side, Ruri kept passing different colored doors one after the other, row after row. In some cases, one door built directly into another. (This place gives me the creeps...) she thought briefly, before finally seeing a dead end approaching.
Stopping abruptly, Ruri inspected the gray wall that stood before her. Even though she hadn't been able to keep an eye on Narumi, she knew that she hadn't taken one the doors along the hall. But if she got to the end, then... Ruri shook her head as she let her hand run over the metal wall. It appeared to be steel, but here, it could've been anything to her knowledge.
"Did she really go this way?" she said to herself. Sighing, she sat down with her back to the wall. But just as she leaned back, she felt the metal slide sideways on her back. Turning around, the wall had opened up a small portion where Ruri had been sitting. Slowly staying in a crawl position, she climbed through the gap. It reminded her of the times when she would play in the local park in the tube tunnel. The darkness was exactly the same too, oddly enough. Squinting, Ruri still wasn't able to see much infront of her, until she suddenly hit something solid with her forehead.
Rubbing her head slightly, she felt around. Sure enough, she found another gap to the right of her location and continued on. A few more feet along, the 'tunnel' revealed an entrance, Ruri peeked through and saw that it lead into another room. A very big room. Clambering out, Ruri got to her feet and looked around. The ceiling itself was probably 30ft upwards, and the distance between all four walls was probably greater. Everything seem to be made of the same substance as before, only this time there was a vague selection of plain wallpaper.
"Narumi!" she called out again. No answer. Observing her bizarre surroundings, Ruri couldn't help but feel tiny in comparison to everything else. However, Ruri pressed ahead and saw something near the opposite wall. She broke out into a run. Upon reaching the other side, Ruri came across an expensive looking glass table, along with a small pair of curtains situated on the wall. The kind of curtains found at the movie theatre in front of the big screen.

"Unless this is the mini screen or something..."

Ruri looked puzzled. As she would be considering the curtains were less than half her own size, only reaching up to her knees. Bending down, she pulled them open, and behind them was another, but extremely small, door. She looked at it in amazement. "Who in the world could fit through this?" she said out loud. She scratched her head as she pulled it open gently. On the other side, she could see an array of trees and greenery. It looked something like a forest.
Unfortunately, at that size, Ruri could only just fit her wrist through the narrow gap, never mind her whole body. Sighing deeply, Ruri couldn't see any alternative. Getting back up, she looked around once again. Narumi still wasn't anywhere to be seen. Ruri then glanced back at the table, and was surprised as she saw a small gold box on top of it.
"Strange, this wasn't here before." She walked over to the table. Opening up the lid, Ruri saw a set of three cookies on the inside, all different colors. One red, one orange and one yellow. But she then noticed something else. Each one had a small bite taken out of it, apparantly someone had been there before her.
(Narumi?) she thought. It could have been her, for all she knew. (Must have been. She wouldn't have fitted through the door otherwise. But... why would she take a bite out of all of them?) Moving the box slightly, Ruri then saw a piece of paper sticking out from underneath it. Picking it up, she read it:

'Eat these, and shut up.'

"Huh?" stuttered Ruri. As far as she thought that whoever wrote the paper must have been arrogant and snobbish, but come on, these were cakes she was talking about. She looked again at the cookies, back at the small door then to the cookies, thricely. "I'm guessing these will make me smaller." she said to herself. "...but that's ridiculous. There's no such thing as a size-changing material." Looking upwards, she fixated on the room. (Then again...) she thought as she saw it's bizarre details.
Sighing, Ruri took a small bite out of the orange cookie, small enough to leave the rest intact. She closed her eyes and seemed to prepare for a change. But it never happened. Then she realized: There was a bite out of each of them. "I guess the order shouldn't matter..." she said as she bit the red, then yellow cookie.
Waiting a few moments, Ruri felt an odd sensation in her stomach, as a bead of sweat lined on her fringe. Once again, she closed her eyes as the feelng intensified slightly.
Opening them up, Ruri felt her body changing. But upon focusing her eyes, she realized just what was going on. She wasn't the same size as normal, but she wasn't smaller either. The opposite, she found herself growing taller. Already, the ceiling wasn't too far away from her head.
"OW!" Ruri cried out as she hit the ceiling with a hard bash. Slightly dizzy, Ruri dropped to a sitting position, rubbing her head softly. She then felt her foot hit the opposite wall, she was still growing in size. She felt her heartbeat speeding up, becoming more anxious about the situation. As her feet pressed against the wall, she felt herself getting pushed back, until eventually she had her back to the other wall.
By some turn of fortune, Ruri promptly stopped growing. Nevertheless, she was taking up the majority of the space, evidently having passed the 30ft mark. Still sitting down, she moved over slightly to get comfortable, putting her legs to the side as much as she could. Rubbing her head again, she noticed she was still holding the cookies in her hand, but she also noticed just how large she was. She felt like a kid in a small doll's house.
Coming to grips with her new size, she felt some heat rush to her cheeks. Even though no one had seen her, she still felt embarassed. It's not everyday one finds themself in this kind of predicament. "Thank you, Captain Obvious..." she said quietly. Bringing up the cookies to her face, she seemed a bit annoyed. "Smaller! Not bigger!" she said to them, hoping they would somehow understand. Ruri gave them another inspection. Then she found something. As she turned the pieces over, she saw that each of them had something written on the back:

"5... 7... 2."

The orange cookie had the '5' written on it, while the yellow one read '2' and the red one had the number '7'.