Robert "Bobby" Cooper was a pre-War criminal who is mentioned in Fallout 4.
Cooper was hired by Winter to kill Johnny Montrano, Jr. after Montrano failed to notify Winter's men that the police were on their way during a job. Winter also ordered Cooper to dispose of the body and ensure that Johnny Montrano, Sr. would not find out who was behind the murder.
Cooper later tried to date his step-sister, but Winter told him to cut off the relationship out of worry that Cooper would divulge some of Winter's criminal activities while sleep talking.
Robert Cooper is mentioned only in Fallout 4.