Weaklings

"Could you do a F2F / Trait swap caption with this picture, please?
The story could be something along this lines:
The girl on the right laughs nervously, trying to hide her dismay. Somehow her nerdy roommate, who she is always picking on, has become stronger than her! 
- Wow! Have you been working out? - She asks while straining to move the girl's arm. She is starting to feel dizzy from the effort, and her own muscles seem to shrink compared with her buff rival. 
- Yeah, something like that - Her roommate replies coyly, while another bit of muscle mass is transferred from the bully's body into hers. When she is done with her, she will be as weak as a kitten! "
---Anonymous

The picture for this caption was also requested.