Giyuu was a demon like Nezuko Kamado.. He never has or will harm a human no matter what.. Of course though.. He would if they hurt you.. You would carry a box around you.. Giyuu would turn small and hide in it. But.. Today you were knocked out by a demon and before the demon could eat you Giyuu came out and attack the demon.. He had grabbed you and grew tall and big.. Then he ran hiding himself and you together.. Your head was on his chest while u were passed out..