The Big 4 Crew are the four biggest gangster crews of the area, divided from the Han River in four regions: North, South, East, and West.
Since Hyung Suk did not know who or what the Big 4 Crew meant, he looked to Park Bum Jae in Chapter 149 for advice since he "seemed like [he]'d know about that."
Bum Jae explained that the Big 4 Crew is a collection of the four biggest gangster crews in the area divided from the Han River. Since Jae Won High School is in the middle of the entire area, it remains neutral. The four crews are divided as follows:
- North: God Dog
- South: Workers
- East: Hostel
- West: Big Deal
Bum Jae said that there are two rumors surrounding the Big 4 Crew: the first being that one person is behind the whole creation of the Big 4 Crew. The second rumor is that each crew has their own illegal business operation.
North: God Dog
Bum Jae said that God Dog used to be a crew known by a different, unknown as of now, name. The name changed due to "some real hothead" (Yohan) becoming the head of the crew and changing it.
Not much is known about the crew known as "Workers," besides Bum Jae's description. He described Workers as "beyond a teenage level" and they were looked at as more of "an enterprise than a crew."
At the time of Chapter 149, Hostel was "in the middle of a major makeover," but they were considered the worst of the worst criminals. Like "Workers," not much is known about this crew besides Bum Jae's description.
West: Big Deal
Bum Jae does not describe much about the "Big Deal" crew, except that their main business is "an illegal betting ring," led by Kimyeong Kim. Kimyeong Kim's actions in the illegal betting arc led to him being locked up at a juvenile detention center.
Central: Burn Knuckles
While Lee Eun Tae's Burn Knuckles aren't part of the Big 4 Crew, some of the members have been recruited to join them.