No one

You didn't want Erica's child so why would you want anyone else's. Karen gives the child up for adoption. Ashley once she learns that you don't want a relationship and to raise the child gets an abortion and finishes college. You learn years later that you knocked up Agnes with boy/girl twins. She never told you as the Doctor she was dating thinks they are his and married her. You go on to a long successful porn acting career. You are pretty sure you father a few bastard children but like your own father you don't raise them. The number of bastards is greatly reduced by plan B and abortion.