Offer to help her.

"Heather," you begin. "Don't worry. I've been through this game a hundred times. I can guide you safely through to the end."

"Uh...you can?" Heather is confused. She was practically throwing herself at you, and you offer to help her? Weird.

"Yeah. And I will, but you gotta do something for me."

Now she's more excited. She knew you wouldn't miss the hint. "What? i'll do anything!"

"I need to borrow a weapon. Can I have your pocket knife?"

She hands you her small knife, looking at you puzzled the whole time.

"Thanks. Now, lemme see if I remember everything right..." You look at your macabre surroundings while Heather looks down at her body, suddenly wondering if she's less attractive than she thought.

(don't worry, this could lead to sex later. be patient.)