Put a stop to it, for now.

With her back pressed so close to you, and the wall of flesh created by the other people at the bar, no one can really see Karen fishing into your waist, deftly popping your button. When her fingers grip your cock, it hardens even faster, and you groan softly.
"K...Karen...."
"Mmm...." she smiles into the mirror. "Hi there."
The rush you feel is part danger, part lust, and it makes your head buzz. It's hard to think.
"Why?...I get that you don't care about Jack..." you whisper in her ear. "But you don't care about betraying your sister?"
Karen scoffs. "Jenna should learn to share. She has everything good." She rubs your tip, and some precum coats her finger. Your heart pounds. "Don't you like it, James?" she turns to wink at you.
"It feels nice, but.... we shouldn't... not right now." Now why'd you say that? Your dick is doing the thinking for you.
Karen's hand suddenly disappears from your pants, but you notice that she sucks on the fingertip that scooped up the tiny glob of pre. "Mm...later it is then." She turns around as Jenna slides up next to you, returning from the bathroom.
"Keeping yourselves entertained in my absence, I hope?" You try to button your pants without drawing attention as you laugh nervously.
"Y-yeah.." you are saved from any awkward questions as the maitre d' approaches.
"Sinclair, table for 4? Your table's ready."