My coworker had been right behind me, so I turned around and said "Do you want to eat here or go back to my office?"
And that's when I realized it was not my coworker behind me, but a young college-age gentleman who simply raised his eyebrows at me.
Surprised, I responded "Oh! You're not with me."
And he responded, "Well, I mean... If you want!"
I then blushed 100 shades of red and giggled uncontrollably, as did the cashier who now thinks I'm a complete nutcase.