(Sag all the way to the liquor store
Where my niggas pour up 4 and get twisted some more)

from Kendrick Lamar – The Art of Peer Pressure Lyrics on Rap Genius

Meaning

They all sag their pants and walk to the liquor store so they can get even more fucked up.

Alternatively, in LA, the term “sag” is referred to driving, usually driving recklessly. So in previously lines he mentions how they are already off a pill and Remy Red, so they are about to “sag” (drive) to the liquor store and “get twisted some more.” .

To help improve the meaning of these lyrics, visit “The Art of Peer Pressure” by Kendrick Lamar Lyrics and leave a comment on the lyrics box