Via either implication of something which was untrue, intentional humouring, or lying.
*got to know them, had sex with, etc

Examples would be saying you're looking for a girl/boyfriend when you're not, implying you might give them a way in at your workplace etc.
Obviously the answer is- when haven't I done this?

And to this I say: Tell me your worst/most morally uncompromising incident. Spill.