You a rebel yourself was caught and sent to the Rebel Correction Facility, or the RCF. Choi San another rebel (undercover) happened to be the one to correct you.

San sat across from you as your arms chained to the metal table so you couldn't use your ability, and you were unable to escape. He glared at you and commented on something, using the rebel code to make sure you weren't just an inconvenience to the government "The weather isn't that great?"