User blog comment:B214/Volume 21 info & spoilers/@comment-82.199.209.161-20160302163726/@comment-195.195.244.67-20160303093154

his eyes are in fact yellow. His eye colour was shown and not ever talked about in volume 4 so his eyes aren't blue like they are in the anime even though he looks better with blue eyes. I bet in the afterword of this volume, Ishibumi will mention he got the eye colour wrong.