The Kallahan brothers moved to our city of crime back in the early days. One decided to become a hired hitman, while the other studied medicine, but dropped out of university halfway through.
It was the hitman brother who took on the name of Killer Kallahan, because of the number of people he had successfully killed. His brother the doctor was outraged at first, until he realized how much money could be made being hitmen.
Although Killer Kallahan could be hired, he was particular about who he bumped off. Once, he was asked to off the local priest, and he refused, even when the price went up. He did have at least some morals, after all.
Living in the West Side, Kallahan would come into Johnny's Joint once in awhile, although he wasn't really a drinking man. Once in awhile, Johnny would have a job for him, so he liked to stay visible.
Killer Kallahan hadn't bumped anyone off in awhile, and was getting a very itchy trigger finger. He always hoped that day would come soon.