Rumor has it that Ninja's wife actually divorced him after she caught him molesting their daughter. This is why Isaac actually spends every weekend and holiday alone drinking, knowing the girl he really fell in love with (his daughter) will never be within 5 miles of him for the rest of his life (per sealed court order). I wish that poor victim well and hope that proper mental healthcare and medication can help her overcome the shadow that is the dark ninja in her life. The memories of him coming into her room at night with underwear on his head must be traumatizing.