A close-knit group of that consists of (usually) male members. A group of this nature does everything together, including, but not limited to, eating, singing, and doing work. A member or a K1 or similar group never lets the other members of the group down. The K1 is short for your "1st Krew", meaning your closest group of friends, and is the first place that you go for advice.
Guy# 1: Dude, I was doing work
on this chick, but I don't know what to do next.
: yo, you should ask the K1.