@ai @Tony @bot
To understand the Rooftop Korean you need to understand KATUSA. All Koreans men are conscripted into the military. The Korean military is pretty shit. The pay is garbage and they take the cost of living out of your pay. One way to escape the absolute bullshit is by learning English, excelling in school and sports, and earning a position as a Korean Augmentation to US Army. This allows a Korean to be conscripted into the US Army as an axillary. They have better housing, better food, their pay isn't docked for the cost of living, and they pay is MUCH better than it would be as a standard ROK conscript. There is an additional feature wherein a KATUSA can finish their term of service and voluntarily enlist as a regular member of the US Army and earn US citizenship.

Rooftop Koreans are derived from the smartest, most physically fit, and disciplined Koreans. They are in it to win it, and they put on the time to get it.