Nothing, Zero, Nada... Used almostly when bragging about not paying for a service or something.
It can also be used as an insult for saying someone is broke.
eg 1. I no get shishi for my phone but MTN allow me make call.
eg 2. Emeka no get shishi for pocket.
You can count on that, it can also mean trusted.
Person 1: Abeg borrow me 5k i go pay you back later.
Person 2: You sure?
Person 1: sure banker
["Sure", " Count on"]