Sadde is running.
There is no particular reason why she is doing this. She just hasn't really done much of anything properly fun for the past five years, at least for the sake of having fun, so the wind in her hair and the occasional glimmer her skin projects on random surfaces when she's hit by the sun are enough.
Until she finds a key.
She comes to a halt and peers at it. It's on the ground, half-hidden by grass, and there's a tree right over there that would have obscured her view had she been running a foot to the right. But as it is, she found the key. It is a very small key, as if sized for a child to hold, and it has a certain shine to it that's not quite like any other keys she's seen during her vampire life.
She explores a radius of about a mile around the key. There seem to be no houses or cabins or mansions or anything like that where such a key might have come from. She returns to it and peers at it, then shrugs and picks it up.
She doesn't pocket it, though, because the moment she touches the key she's quite certain it's a magical key.
It doesn't actually do anything, it doesn't explode or shoot fireworks or glow, there's no mysterious voice saying that he has found the Artifact of Doom or anything like that. She just—knows.
When she straightens up, she notices how she knows it. There seems to be a certain sense produced by the key, a feeling of sorts, that shifts and moves about as the key is moved through the air. She waves it around a bit, and reaches two conclusions: one, most spots in the air don't feel like anything; two, what a spot in the air feels like depends on the spot itself, and if she waves the key around a given spot multiple times she feels the same thing each time.
O-kay, this sounds fun. Now what does the key actually do?
...well, it's a key, presumably it opens doors. It's a magic key—does it open all doors?
After thirty minutes—during which she runs to the closest town, finds the least observed door, and tries to open it with the key, followed by several further attempts on several different doors—she has determined that the key does not in fact seem to have the property of opening all doors.
She has also determined that locks consistently don't feel like anything to the key. Which seems to suggest that, if she wants to use it, it's not going to be on an actual door. So she decides to try the obvious thing. Except not here, this is not a good place, so she finds an isolated spot in the woods to try the obvious thing.
Upon finding an appropriate isolated spot, she waves the key around until it feels like something, then she pushes it and turns it, as if she were unlocking an actual door.
That one works.
She pulls it, and the door opens before her. And the image on the other side is... quite fantastic. A frozen lake—ocean?—with water everywhere, and a few floating rocks in the distance, with—are those houses?—on them. She removes the key from the door—good, the door still exists—and gingerly steps onto the ice, wondering whether it can hold her weight.