Answer:
Deviant; Deviant act.
Step-by-step explanation:
Deviant is an act of deviating or straying from the accepted standards or norms.
Killing, where, in a society is considered a deviant act, not killing in mafia's is an act of deviant.
Honor killing is an act of killing or murder of a person, whom people believe to have brought shame or dishonor to their society.
In Mafia's killing someone who brought shame or dishonor is an act of honor, hence named, honor killing. And not killing or murdering such a person is a deviant act for them.