User blog comment:Betapekoyama/Portrait Requests/@comment-28583560-20160531041249/@comment-27617011-20160601214757

I think she means like Mai's eyes, which cycle through the various colors of the rainbow. However, since it's a still picture, it's impossible to do such (Mai's portrait shows pink eyes, which was her original eye color). I'd say just pick your favorite color and go with that.