If you scour the publication information on the title pages, back covers and inside book flaps of graphic novels, you'll often find either a numbered list of suggested subjects (the Library of Congress subject headings), or a series of subject suggestions for where to shelve the book in question in your book store.
For example,in Aya, you'll find subject suggestions of "teenage girls," "Cote d' Ivoire," and, the most common one among graphic novels, "Comic books, strips, etc." In The Magical Life of Long Tack Sam, the subjects are "China," "biography," "comic books, strips, etc." and "Long Tack Sam."
For this book
a wonderful debut graphic novel by Tim Sievert with a quite powerful emotional story (plus a giant octopus coming into conflict with a man, one of my favorite story elements in any type of comic book) and great black and white art, the subject suggestions, are, I imagine, at least somewhat tongue-in-cheek.
They're not on the title page or numbered like Library of Congress subject headings, but appear on the back cover.
Here, take a closer look:
I would love to visit a book store that actually has an "oceanic revenge" or "seaside heartbreak" section.