Stephanie offers to sing you to sleep, you right there on the couch, and you accept, since you're rather tired and the beer has been getting to you anyway.
She sings a funny song, something about, "O Daniel, be my Clurarcon, o turaluralay. Small as a mouse, big as a house, my friend for night and day."
It's a pretty song, but very odd, but you find it comforting and you fall asleep. You awake to the sound of a hammer gently tapping and open your eyes to see Stephanie on the couch opposite you, busy resoling what looks like the entire content of your shoe closet. "Top of the morning to ye, Daniel, me cluracan," she says happily and you notice she looks a lot larger. So do your shoes, for that matter, and the couch she's on, and the couch you're on for that matter, an enormous sea of upholstery.
You suddenly realize that just like she sang, you're small as a mouse! "What did you do to me?" you wail.
Stephanie smiles. "Well, Daniel me friend, you wished t'be me friend, so I got to thinking what would be the best present I could get for you, an' also how us little people don't make friends with the big folk too often, since it often ends badly like as not. But then I thought I'd make thee a gift an' make you one of the wee folk yourself."
You look at how enormous your house is now, then exclaim, "I'm a pixie!"
"Don't be daft," Stephanie tells you, "pigskies have wings. Besides which, they tend to be flibbertigibbets. I don't have much truck with them. Yer something much better--yer a cluracan."
"A who?"
She grinned. "Yer a sprite wot kin change his size as he wishes, from small as a mouse to big as a house, though I suggest ye not get much bigger than this room at present."
You look at yourself and try to will yourself to get bigger, but nothing happens, until at last Stephanie giggles. "My, don't you look a sight. The way I see cluracans do it is by sticking their thumb in their mouth and blowing until they puff up like a toad or an adder.
This sounds particularly insane, but you try it, and find that it's like inflating a particularly stubborn balloon, but you find yourself slowly getting larger. Finally, after about a half-hour of hyperventilating, you're back to something around your old size, maybe a little bit under, maybe a little bit over. You flop down on the couch and sigh in relief, noticing that the sigh continues for a long while, like a car tire with the air being let out of it, until at last you catch your breath, stopping your shrinkage.
You're now definitely under your old height, but still something okay for an adult human, and Stephanie giggles. "It will take some gettin' used to, no doubt, but it's a fun trick, and it's not as if I could teach you the secrets of fairy cobbling in one night. This is an art." She smiled. "But to make it easier on you so you don't need to keep panting so much, I fixed up these shoes fer ya, Daniel."
She holds up your pair of Air Jordans. "See? You can just pump them up an' yerself as well, my fine cluracan." She grinned. "And won't you have fun on the basketball court."
You stand up and bounce in the air, almost bumping your head on the ceiling, but not because you're so tall, but because you're so light. You suddenly realize that though puffed up to human size, you don't weigh much more than you did at mouse size. But you gratefully accept the shoes from Stephanie, putting them on and pumping until you inflate enough for them to fit, then keep pumping, standing up and having inflated yourself into a very light but very tall basketball player.