Tinker's damn

The damn or other curse issued by a tinker. 19th century language in which tinkers by trade were considered some of the lowest in society, so to not receive a 'damn' from a tinker is considered as being lesser that the lowest. The modern day equivalent to tinkers would be furries, so if a furry doesn't give a damn, you gotta be one sorry son of a bitch.

I don't think you're even deserving of a tinker's damn, after what you did to those kids.