The holding of excessive feelings of sympathy, solidarity, goodwill, etc. by a victim of a crime towards the perpetrator of the crime. The syndrome takes its name from an incident in Stockholm in 1973 in which bank robbers took hostages, and after the incident was resolved, the hostages defended and even married the criminals.
During the Shadow Moses Island Incident, Snake mentioned this syndrome when pointing out the fact that the hostage, Hal Emmerich, had developed a slight attachment to Sniper Wolf, a member of the armed group that had occupied the facility. While taking care of Sniper Wolf's wolf dogs, Hal realized she was lonely. He begged Solid Snake not to kill her, but it was unavoidable for the execution of Snake's mission.