Oni no Ou to Chigire - Chapter 7 Pg 129

He said right after he came home from the hospital, so in other words, a few days after he was born. Yato had been by his side ever since he was born. A newborn barely had sight, let alone visual focus, but he had heard a demon master baby, while unable to recognize the face of their own parents, could immediately recognize a demon. Since they could also hear a demons voice perfectly, it probably wasnt a coincidence Tokimori reacted to Yato calling to him. For reasons unknown to him, the natural thought, aah, I really am a demon master, finally sank in. Perhaps glad Tokimori, who insisted on not talking, had spoken to him, Yato began to talk about the times Tokimori would have no memories of at such a young age.

I knew you were scared of me. Even though you were a baby who couldnt talk yet, every time you looked at me, youd make a terrible face and cry. I wanted to do something about it somehow, so I would sneak into your home when your family wasnt around and make funny faces at you

Y-You came inside the house!?

Tokimori interrupted him. He reflexively looked up at Yatos face, but ended up lowering his head frantically. The hair all over his body stood on end. Since demons always stayed outside of his house, his innocent, young self naively believed he was safe inside his home, but now he felt afraid.