With a little encouragement.

"You...you...you're a slut," Sam says, trying to be mean.

Liz looks at her sadly, knowing that she has ****.

"Good. More," Donna says, "Tell her why you know that she's a slut."
"I...I saw you with Mark in the Supply Closet," Sam adds, "You were taking him in the ass while he choked you."
"Ooh, kinky girl. You like it in here then, huh?"

Donna starts to finger Liz's asshole again, something the latter secretly loves. She's mad at Sam for revealing her weak spot.

"Tell her to suck on your tits. Be assertive."
"S...suck on my tits," Sam says, "Do it, you...you slut. Do it like you did for her."

Liz nods and takes Sam's right breast as it is presented to her. While still tied up, Sam can still make Liz do this for her.

"Enough pleasure for her," Donna says, stopping the fingering, "This is a new challenge. Keep track of any and every time you feel teeth, Sam. Be honest or you'll suffer."
"Yes, Mistress," Sam says, moaning a little at what is being done to her.

Her question of why she would feel teeth is quickly answered when Donna starts spanking Liz. She does it hard and fast, but sometimes slow and sudden. Liz can never predict the timing or ferocity of the strikes.

Sam winces as she occasionally feels the sting of teeth on her breasts. She keeps count, not wanting to face the consequences of what Donna might do to her...

http://img171.imagevenue.com/loc1132/th_68568_TheTrainingofJadeMarxxxDay2_123_1132lo.jpg

Several minutes of this go by before Donna stops and signals for Sam to move her tits away from her friend.

"How many times did you feel teeth, ****?"
"4 times, Mistress. I'm sorry, Liz!"
"Don't be sorry if you want to be a Mistress or, at the very least, not on the bottom. So here is what that number means to you..."