"Oh, yes," David said, grinning evilly. "I really would."
 
He began pouring most of the powdered potency into a glass.
 
"How much do you think I should put in, hm?" He asked, nearly sweating. He was pretty fat by now, so most of his movements were enough to make him sweat. In spite of her situation at the moment, Katherine loved to see him that way; she had fattened him enough. Perhaps she could escape if he had gotten too tired!
 
"You should just let me go before something bad happens, fat ass," Katherine spat, struggling to get out of the chair. This wasn't going as she planned at all.
 
David shrugged, mixing in all of the powder with some high-fat milk, a sadistic grin on his face. This would make her just as big as he was, maybe even bigger! He made his way back over to where Katherine was, sweating more visibly.
 
"Your turn to be the piggy," He said, forcing a funnel into her mouth. He then began to pour the weight gain drink down her throat.
 
Katherine had no choice but to swallow. For such a malicious sort of shake, it was tasty, she had to admit. Eventually she wanted more of it and began drinking without problems, for the most part. David laughed every so often, observing her fluid-filled stomach peeking out from under her shirt. It was beginning to get swollen.
 
Finally, Katherine had finished. She took a deep breath, some of the shake sliding down her cheeks and to her chin. It sloshed around in her bloated stomach uncomfortably, but she hadn't seemed to have gotten any fatter. Not immediately, anyway.

David read the label. "Hmmm... why isn't this working...?"
 
 
The label says...