Blue
A color of the realm of the gods. The thoughts [spiritual energy] and Pure Eyes [Jougan, 浄眼] of those whose existence approaches the realm of the gods are of this color.
Red
A color symbolic of demons. The thoughts [spiritual energy] and eyes of those connected and intertwined with demons have long had the tendency to be this color.
Adept
① Written as Adept.
② Within magecraft-related organizations “adept” refers to an expert or master level individual, or to an individual who has unraveled some of the deepest, most secret techniques of magecraft.
③ “Adept” is thought to be something like a title that is conferred upon such individuals.
④ In some fantasy stories, the title “Adept” is held by monks in a similar fashion.
Oni Child
① Result of sudden mutation. From the moment they are born, you can feel there is something different about them. A deviation from the norm in the family or group.
② In the world of Tsukihime, in which oni kind exist, the word oni-child doesn’t actually refer to the children of oni. Rather it is a discriminatory word carrying the meaning written above in ①. In reality it has often been used to persecute humans with special powers.
③ “Oni-child” also has the meaning of “A child who doesn’t resemble his or her parents,” the term was probably used in a similar manner to this.
Oni Kind
① There are two types. First, those who are fundamentally different than humans, as in they existed as oni from the very start. Second, humans born with mutations that become oni.
② True demons.