"Blow this" he thought. That was enough! She wasn't really all that good looking and he was sick of feeling used.
"Wait here."
The command worked, even only if it was because the shock of being instructed to do anything by him caught her unawares.
He sauntered up to the first person he saw.
"Hi there!"
"Ugh... hi?"
Not put off by the stranger's confusion, he clapped a friendly hand on the stunned chap's shoulder and pointed over to her.
"I thought you should be the first to know, I'm breaking up with my girlfriend."
With a couple of pats on the shoulder he strolled off and left two utterly gobsmacked strangers staring at each other in the crowded street.