"What are you going to do next?" Tina whispered to herself before turning to Leah, "Poop your pants?"
While it was technically a question, Leah only heard the second part, and it was spoken as a command. Even if Leah knew it wasn't, her brain didn't, and that was all it needed to follow a command. Leah, still wheeling from her earlier accident, lurched forward into a squat and pushed. It took her a second to realize what she was doing as a puff of gas came out her butt. She didn't need to poop especially bad, so she has to push. That gave her some time.
"Tina, tell me to not poop my pants."
"What? Wait, what are you-"
"Please, Tina!"
It was too late. Leah grunted as she deposited a lengthy log into her soaked panties, followed by another one slowly being pushed out. Tina's jaw drops and Leah starts crying as the log pinches off, leaving a lumpy mass in the back of her pants.
"Leah, did you just-"
"Why didn't you say it, damn it!" Leah shouted, crying and embarrassed. Tina was mostly just confused; that was no accident---Leah had purposely pooped herself---yet she was acting like it was one.
"Leah, what are you talking about? Why did you-"
"Tina, you don't understand, I can't control it!"
"You...can't control it? Since when? I know you were having a handful of accidents, but-"
"What, no I haven't! Why would you- ugh, Tina, I didn't have an accident."
"So you did it on purpose?"
"Yes- I mean, no. I had no choice."
"It sounds like you might need soem potty training."
"N-No, no I don't! I do not need potty training!" Leah called out, worried the conversation was getting into dangerous territory. One misspoken phrase, and Leah would be powerless to stop herself.
"You...don't? This is news." Tina said in a peculiar manner. Leah decided to cut her losses and bolt.
"I'm going to go get cleaned up, okay?"
"Oh, Leah, you'll need protection won't you? You said it yourself, you aren't potty trained."
The statement was spoken, and Leah felt her brain twist around.
"W-When did I say that?"
"Isn't that what you meant by 'not needing potty training'?"
"N-No, of course I-" She cut herself off as a disgusting squelch filled the air. Leah frowned before grabbing the back of her pants, and felt the bulge getting bigger. She let out a grunt and realized she was pushing. Why hadn't she noticed? She had to 'poop her pants' before, but she could stop. Now...she couldn't. Because Tina just told her she's not potty trained. Leah paled. She needed to come clean, and just hope Tina didn't abuse her power, or else she's going to be stuck in diapers.