She can't

A mantra echoes in her mind, one that her ex told her after every edge he put her through in this position, and as soon as it shows up in her mind, Alice whispers it into her ear.

"Good girls don't cum." Alice whispers

Sam almost explodes hearing those words, but she can't cum, she's a good girl.

Alice takes off Sam's gag, leaving a string of drool as she moves it, "Go on" Alice says

"Good girls don't cum, Good girls don't cum, Good girls don't cum." Sam repeated it for every edge Alice brought her to. She was in heaven.

Sam opened her eyes to a concerned looking Alice. "Sam! You passed out, are you okay?"

Sam felt so lightheaded she thought of needing water, and a water bottle appeared to her side, created by the same translucent material that made Alice. She guzzled it down with fervor. Once it was down she felt so much better. Sam realized that she couldn't let that happen again without some safeguards, this void was completely different to her world and Alice wasn't her ex who took perfect care of Sam when she was edged.

"I'm okay" Sam said, "Sorry Alice, guess I got carried away"

"It's okay, you don't need to apologize to yourself. We had a lot of fun." Alice replied.

She's right thought Sam It was my fault, I need to be more careful. It was really fun though.