This volume is all about curiosities held by Hell's residents! Shiro's curious what sort of place is the authentic Hell Hot Springs are really like. Momotaro's curious to see what the deal is with this so-called “folktale folk meet-and-greet.” And Karauri and Nasubi are curious to find out more about a certain jiangshi named Chun, King Godo Tenrin's aide and the model for the heroine of a popular manga. Don't let her cute face fool you, she's so ferocious that even Hozuki's no match for her. What's more, she's Hakutaku's ex-girlfriend?!

More Mao Hao Hao, more fun! Volume 12 marks a huge milestone with the series' 100th chapter! In this monumental edition, Hozuki shows great interest in the legends surrounding King Enma, while the others show great interest in the antics of a 15-year-old (in human years) Hozuki, skipping class to check out a cursed club. Meanwhile, half for business, half out of morbid curiosity for cruel fairy tales, Hozuki heads to Heaven to have a chat with the goats of The Wolf and the Seven Young Goats. And at long last, the names of Hozuki's two lifelong friends are revealed!

The mural of Enma Palace is crumbling! Families are offering too many oblations to the dead! Beelzebub’s wife and master seductress Lady Lilith visits Japan from the West! There is no problem that Hozuki can’t solve. Well, apart from constant headache Hakutaku gives him, perhaps.

Volume eight opens appropriately with a tale of the Eight Cold Hells! In this edition, we review the similarities between the Greek and Japanese underworld, eavesdrop on King Enma and King Shinko grumbling about their respective aides, sit in on a conversation between Hozuki and Hakutaku on the intricacies of badmouthing, and get a peek into the life of Kakisuke. Volume eight, now with nine laugh-packed chapters!

In this tenth edition, Hozuki is invited to give a presentation at an elementary school, fills in at a mixer at the behest of Karashi, investigates a group of ogres terrorizing the mortal realm, and even has to deal with Haruichi, a spy from the Eight Cold Hells. As if he wasn't busy enough, Hozuki still finds time to drop by European hell to give Satan a piece of his mind for sending King Enma a most offensive missive!

Hakutaku's mortal realm fashion sense is so lame, he looks like an old man going for a game of gateball! There are so many animal wardens in the Shoko Court, it looks like a scene out of a nature documentary! Karashi's backstory is too terrible for words! And as usual, the zashiki-warashi twins are too darn deadpan!

The Jizo is an avatar of King Enma? There's a special hell for sending an elephant on a drunken rampage?! Learn these and other veritably useless Hell trivia in this eventful edition! We've got a goldfish plant pageant, a day in the life of Shiro, a look into Hell management, and much more! And what's this? It turns out Hozuki is actually King Enma's second aide?!