As a teenager she would 'sneak' out (of her house/apartment) at night to visit her boyfriend.
I'm going to 'sneak' a smoke. [=I'm going to smoke a cigarette while nobody is watching]
She took a 'sneak peek' [=a secret look] at the birthday presents hidden in the closet.
(..) - What? Loading and unloading airplanes. Wow. Do you get free tickets then? Are you going to take me on a trip? What? Maybe you can just sneak me into the Duty Free. To me the transit area is even more fun than going abroad. It's like you've started a journey but everything has yet to happen. (..)2015 Virgin Mountain