She collars her

She stares at Hilda for moment, contemplating what to do with the naked woman and then snaps her fingers.

“I know!” She says before getting a rather sinister look on her face.

Hilda shivers in fear for a moment, dreading what she has in mind.

“And I've got just the thing...”

She turns around and starts rooting through her backpack, returning a moment later with a piece of cord tied to a simple collar and smile on her face.

“You're gonna be my pet for the night.”

Hilda sputters and spits at her demand trying to refuse it, but before the words can come out, Milly's already put the collar on her.

“Now then, as long as you wear this, you'll obey my every word. Understand?”

Hilda's face burns with humiliation, and she can't bear to look Milly in the eyes.

“...yes,” Hilda mumbles.

“Good. Now then, get on all fours and...”