Responses
He is definitely not a child but you probably consider him mentally somewhat a child. When Isaac is telling Giselle his back story he was sold Giselle's husbands father. That makes him at least around Giselle's age or older (I'm guessing older). He only looked like a child at the beginning because he was severely malnourished. After feeding off of Giselle regularly he grew.
so is isaac a child or is he a grown man because the way she treats him as child is making me (⊙…⊙ )