Yang Yi entered prison because he wanted to become a spy.
Yang Yi didn't belong in prison, nor would he mix with street gangs after leaving, much less stoop to drug trafficking.
To Yang Yi, prison was just a school; he didn't want to waste too much time there, nor did he want to waste any emotion on those scum.
"I'm sorry, I don't want to join the gang," he said decisively, rejecting the invitation from the Latino man in front of him.
Although unfamiliar with the prison, Yang Yi wasn't an idiot. Even without Chris's warning, he knew he should never get involved with the gangs inside, for they were extensions of the gangs outside. Joining one meant becoming a part of it, unable to rid himself of them even after release.
Moreover, joining a gang required a test. What kind of test? Of course, it meant making a name for oneself, the simplest being to stab someone a few times. If you had the guts to knife someone, and didn't rat anyone out, then you could join the gang.