Swallowing it won't help

"This is disgusting," she thought.  The stuff was everywhere into her mouth, touching her teeth, rubbing on her tongue and palate.  Some was dripping down her chin, falling through her wide collar and landing on her breasts.

"I can't stop now, I've got to finish it."  The only thing she wanted to do was spit it out, but she couldn't bring herself to do it.  She just wanted that thing out of her mouth, but she knew there was no point in doing that, since she'd have to do it again later.  She had to get accustomed to it, even though she hated it.

"I can't swallow that, it tastes disgusting.  It can't be good for my stomach."  Even if she could convince her mind to swallow it, her body would never accept it.  The gag reflex had been triggered three times already since she started.  She would vomit before being able to swallow that.

"Come on, bear with it!  It's not that bad," she tried to convince herself as some of the substance slowly moved in her mouth.  She flicked her gaze upward and met the other pair of eyes.  They stared intently at her.

"It's almost over now, almost--"  She stopped as she started choking.  The liquid had gotten into her windpipe as she was trying to breathe.  She spit it out quickly.

"Ugh..." was all she was able to mutter.  After a while she looked back at her reflection in the mirror and, seeing her face all splattered with the white mixture, said "Goddamn toothpaste... this stuff is disgusting."