Oni no Ou to Chigire - Chapter 2 Pg 43

There were only a certain amount of human traits, but the variations of demons was abundant. There were ones close to two meters, or around one centimeter, ones with six eyes, and four arms. Blue and red were popular skin colors, but they were every color imaginable. Having to see those grotesque forms all day and night, Tokimori spent his days crying in fear until he was five. If they would have just treated him like a fly on the wall, or just passed him by like he was nobody, he could have dealt with it, but all the demons he could see would watch him, so whenever they tried to meet his eyes hed get even more scared. Without looking away, the demons would face him with a wide smile and tell him they were going to rip him apart with their fangs as they showed him their long sharp fangs. His parents and grandparents who couldnt see demons couldnt understand Tokimoris fear. No matter how many times he explained how strange the physical appearances of demons were, or that they scared him, since they couldnt actually see them, they couldnt understand just how frightened and disgusted he was. He now thought that they may not have wanted to understand. Tokimori had a feeling that was exactly it. That was because a demon masters rank wasnt decided by their age or purity of blood, but by their ability to command demons. A demon master was to make a contract with a powerful demon with no ties to the main household or other branches of the family, and assume head of the family to lead the Yase clan down the path to greatness. The Yase family got together to make Tokimori choose a strong demon, since he was the only one who could.