User blog comment:B214/Volume 21 info & spoilers/@comment-112.215.152.120-20160620030134/@comment-9595671-20160627001826

And we only got see Loki's appearance through the anime, the only way I feel we'd see what all the characters would look like is if we got some major artbook for the series showing character sketches. Unfortuantely, that doesn't seem likely if the novel illustrations are getting lower.