Give them back, but keep some as collateral

You undo the restraints on the chair, and grab her clothes, placing the stack in front of Evellyn. The fact they're neatly folded feels like an additional slap in the face, one you delight in.

"There you go."

Evellyn seems a little surprised you're actually giving them back. When she reaches over to grab them, you interrupt her "I'm gonna keep these though," holding up your hand to show her the bra and underwear you've get clenched between your fingers.

"Bu- "

"Consider them hostages; to guarantee good behaviour."

Evellyn rolls her eyes in aggravation. Grumbling, she quickly gets herself dressed while you watch, unable to prevent exposing herself time after time, slipping her overclothes directly over her naked form. She's forcibly going commando.