184.108.40.206 22h01min de 26 de Setembro de 2016 (UTC) A Kakugan (Japanese 赫眼, English shining eye) denotes a ghoul's eye where the pupil turns red and the sclera black. The ghoul can enter this state by their own will, but this state is also entered when the ghoul becomes excited or when they use one of their special abilities. A kakugan is a result of using Rc cells.
Generally, a ghoul possesses two kakugans and they always activate together. If a subject possesses only one kakugan, they are a one-eyed ghoul. A new type of ghoul/human hybrid called a quinx possess only one kakugan like a one-eyed ghoul, but their sclera is grey instead of black
fontes: Tokyo Ghoul Fanon Wiki