Yasusada: He's technically just a sword(spirit) but I guess his dad would be the one who forged him. and that man had some skills cause Yasusada is a strong and sharp blade :'>
Mammon: T-technically his dad would be god??? They never use the term God in Obey me, just like Father and the one who created everyone. But it's pretty much implied to be god.
Izuminokami: Also similar to Yasusada because he is a sword(spirit) so his dad would be the one who forged him. And that man knew how to make a beautiful sword~ lmao
Susumu Both of his parents died when he was young, so technically his older sister would have been his mom and dad. Because she raised him. I'm not sure how old he was when they died because he does seem to remember them and mentioned that his father was like a pretend doctor when undercover at one point