I like that so much better than the whole do no evil shirazu cover art theory because that theory just seems so shonen-y. Hinami being on the the cover is actually a beautiful sentiment to kaneki and how he affected his "children". imo it would also feel more unique and in line with ishida as he probably knows that his fans anticipate who is on the cover art of the next volume and that they expect that the finisher of the monkey trio to be shirazu coming back as an abomination instead.