"Yukiko? What are you doing in here?" You hear from outside if the closet, the voice you can't recall, mostly from being so scared.
Yukiko snaps up, a worried expression on her face and turns to the voice. "Oh, I was just looking for something." She said, her voice slightly trembling.
"Well, come back to the party, I don't think Ben would be too happy with you snooping around like that."
Yukiko looked back in your direction, almost directly at you, and you started jumping and waving, hoping to get her attention. But it was useless, as she turned back to the voice and said "yea, okay, I'll be right there."
You heard the footsteps of the other giant walking off, and Yukiko scanned the closet one last time. Still not seeing you, she whispered, "Okay Been, hide in here as long as you need to. I'll be back for you before I leave, okay? Be safe." And she blew a kiss in the hopes you'd see it before closing the door, and leaving a small crack.
And that was it. You'd just been abandoned by the only person who knew what happened. At less than an inch tall, in your closet, alone, you sat on the ground, and cried. You were scared, helpless, alone, and had no idea what to do next.
But you remembered that you had left everyone's purses in your room, just for safe keeping. You could get to those, maybe find Yukikos and garuntee safe passage to a better place to get her attention.
You could leave your room, go out to the party and maybe find her, or some other help, but that could be dangerous with the people you do and don't know. Who knows how they would react if they found you.
Or, you could wait here. She said she would be back, right? It would be the safest option, albeit the most boring.