She does so.

Her sensory range isn't far like this...

But they know an opponent's there. They might have surprise, even, if the person's expecting another vampire.

She opens the entrance.

She can perceive the person on the inside whirling around, presumably to face the entrance.  "Who's there?" he calls.

Sand blasts into his face, forcing its way into eyes and mouth as Gaara reveals herself.

(Detail work like this isn't easy, but Gaara's been practicing).

He starts trying to shout something, but the sand chokes off his voice.  He draws a knife and slashes wildly through the air toward where the sand is coming from, and starts backing away blindly.

She aims to trip and then bind him - enough at least Nausicaa can get cords and a gag on him.

He slows, walking deliberately enough that he's not liable to slip even on a thin layer of shifting sand, pointing his knife towards Gaara.

And Nausicaa moves behind him to trip him with a sweeping kick.

He falls to the floor, and in one motion rolls over onto his front and starts raking his free hand through the air, looking for Nausicaa's leg.

She jumps out of his way and then as Gaara's sand comes down goes to help pin him.

There's little else he can do, at that point, but struggle vainly against her pin and against the weight of the sand.

Then she'll try to get him gagged and tied up with the cords she brought.

As soon as the sand flows out of his mouth to make room for the gag, he shouts, "intruder!"

...Shit.

She gets him gagged fast.

Anyone coming?

As she's standing up, the door opposite them bursts open - an unfamiliar vampire dashes in, a throwing knife in each hand, and as his eyes rake over the scene in front of him he pitches one of them expertly toward Gaara.  He starts charging Nausicaa while the knife's still flying.

She turns into sand and falls to the floor, the knife sailing over her, and rematerializes in a crouch.

And Nausicaa leaps for the new dude.

New dude brings his knife-holding hand up in something like an uppercut, aiming to stab Nausicaa in the stomach as she collides with him.

She twists, punches him in the solar plexus.

He gasps, but seems unimpeded by not being able to breathe; he spins to face her, transfers the momentum from the turn into a roundhouse gut punch.

That clips her as she jumps back again, dropping to try to trip him - 

As Gaara flings a solid ball of sand at the back of his head.

He trips, falls, but turns his fall into a forward roll, and as he’s springing to his feet - 

She turns into enough sand to bury him.

She has to plan this - she can't change her mind while being sand - but once she's calculated he'd be down she turns back into human-shaped, crouched on his back.

He manages to lurch to one side as he's bowled over - he doesn't land as gracefully, but he's not properly underneath Gaara either.  He shoves himself away from her and lashes at her leg with one arm at the same time, throws her off balance -

She tumbles, falling and hitting the floor hard enough to bruise - and she's not particularly graceful getting back up -