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.
(..) But forget what you heard I'm like James Bond the Third Shaken not stirred I'm Kevin Gnapoor The G is silent when I sneak in your door And make love to your woman On the bathroom floor I don't play it like Staggy You'll know it was me Because the next time you see her (..)2004 Mean Girls