a Korean subculture; similar to the Japanese yanki.
Yangachi is a hard-to-define persona, but can be said to include various outcasts in school, in social groups, or in all kinds of modern people's entities made by usual interactions. Yangachis intentionally decline to assimilate to major trends, and strictly follow their own ways. They will be involved with sleazy crimes, like blackmarketing, drug packaging, extorting from small business owners, protecting whores from 'naughty clients', even meddling with local gangster ('Jopok' in Korea) business. Most Korean youngsters have some fantasy towards becoming a yangachi, but are totally banned from becoming one by their schools, or by their parents.
The yangachi was labeled a hoodlum by some and a menace by others.