No Mercy for the Rude (2006)

A lonely chef with a speech impediment takes a job as a professional killer in order to raise the money he needs for an operation on his tongue. Known as Killar, he and his partner Ballet, make a rule to only kill rude and impolite people. After killing each one of his victims, Killar goes to the same bar where he meets Her, a woman who becomes attracted to him. His life begins to unravel after he and Ballet kill the wrong person by mistake.