She refuses

"I am not taking my shirt off for you," Supergirl says, crossing her arms against her chest and trying her best to look far more confident than she felt.

"Is that a fact?" Captain America replies, taking a step towards her. "So, there's no honour to Supergirl huh?"

He pauses for a moment, before slipping his phone into a pouch on his belt. "Oh well, I'll just have to think of all the various places I can post that picture won't I."

Supergirl felt her blood run cold. "What?"

"You heard," Cap said his voice cold as ice. "If you don't want to pay up, then I guess I'll just have to be sure to use the photos as best I can."