GLLT BOW

This was created in music, specifically Hip-Hop. Not just Hip-Hop but Drill Music. Drill music was formed in Chicago originally but then spread all over especially NYC, Specifically Brooklyn. Drill Music artist like Pop Smoke, Rah Swish, Fivio Foreign, Sleepy Hallow, Sheff G, Rowdy Rebel, Fetty Luciano, Booby Shmurda & On Point Like OP have used this phrase in their songs frequently. Now rappers from all over also quickly started spreading this phrase as well. It basically goes with the vibe your in, it could be a dark diss vibe where it turns into a gun sound or it could be based on a good vibe like hanging out and just vibing with the party and you would hear people scream GLLLT BOW. It depends on the situation and mood your in.

Hanging out, Partying and having a good time.

Mike - Yo tonights gonna be a movie brooooo
Sam - YKTV brodie GLLT BOW

Or as a lyric in a song.
"Shoot the boy up all he heard was GLLT BOW"