KHR: Volume 34 is probably my favourite Primo + Decimo cover. The lighting of the sword is well-done, and I love the blue theme.

Let's not forget that Yamamoto's smirk (?) won me over.
Beelzebub: I like the chapters in this tankobon, but the cover is meh. :/ The pink-yellow gradient could've been left out.
Hokenshitsu: Who are those two characters? It makes me sad that Hokenshitsu's rankings are low and that it'll take a while for the chapters to catch up to that point.
Nurarihyon: Aww, Rihan and Yamabuki Otome are holding hands!! I've always liked the simplicity of the Mago volumes; never overdone.