To excessively overthink an action or decision to the point of confusion in ones ability to make the choice.
I cannot decide what loafers to choose, I am really nikki-ing this decision.
I have done so much nikki-ing trying to decide what colour to paint my big toe.
The act of accepting a mans invitation back to his house just to get free coke and sneak out.
Bro I gave her a line and she hopped out my window she Nikki-ing