@Century_Orion no, Parthenos is only Virgo's adoptive mother. I'm saying birth mother.
From what I can tell, this is what happened:
OG Lufasu got beaten by heroes under the goddess' influence and sealed away, that seal made them get "reborn" in our world (or our world was simulation for them so that Lufasu thinks they are just a normal human, thus, hindering her real power not understanding how to use herself fully), that version simulates the events of his/her life in a game and then is brought back to their world in the unsealing.
Basically, OG Lufasu and the player male character are the same soul/person, but Goddess' fuckery has caused memory issues. And, yea, I'm suspecting at some point OG Lufasu did have a kid, Virgo, but can't remember atm cause of the memory issues. The question would be then, who is the father? The whole mana issue and her level being so high seems to hint it was Lufasu's mana/genetic influence.