Talk:Ken Kaneki/@comment-24259054-20140605231239/@comment-24494906-20140605235554

After these events, Kaneki often is in some sort of ghoul mode. Thus, his kakugan typically shows, his left iris is red. (In one of the covers, the right pupil also glowed red, but I haven't seen it in any other color page). That's why Kaneki's eyes appear to be different after the Aogiri arc. But I think the more time went by, the more often Kaneki deactivated his kakugan and his eyes went back to normal.

(Ishida also draws "surprised" eyes similar to Kaneki's kakugan eyes, so it's not always clear which of these two effects make Kaneki's eyes appear this way.)

After the Aogiri arc, the appearance of Kaneki's eyes is a sign for his current mood. If his kakugan is activated, it's a sign of alertness or readiness. If it's not, then he is relatively relaxed. For example, Hinami's presence seems to have some sort of soothing effect on him, so his kakugan always deactivates when he interacts with her.

This kakugan (where only the iris turns red, not the one where the whole eye turns red) rarely showed before the Aogiri arc. I remember that it appeared in Kaneki's fight against Amon and I think he also showed it while he fought in the dismantling show.