Denji is your father which is the famous Chainsaw devil user, he did it with your mother Asa Mitaka at a young age as a dumb teenage boy. When he discovered your mother was pregnant with you he decided to take responsibility for lots, your father Denji before you were born also had thoughts like “What if I’m not gonna be a good father??” And “What if I do something wrong and my daughter/son hates me?..” As a kid Denji was abandoned by his parents so he had no idea how to parent..