The landlady Mikitty is back, and she's even more bizarre than before. Ostensibly checking in to drop off a notice of impending construction, she hints at what might be behind all the robberies and attacks that have been going on lately.
But Maou hardly has time to wonder what's up with the creepy landlady. Once again, Chiho-chan has the completely wrong impression of the relationship between Maou and Emi, and has run off.Bes
And then, another earthquake strikes.
Turns out, The Devil King Maou has company. His former general Lucifer has somehow made his way to Earth, and wants to take it over for himself. And even stranger, it looks like one of the six Archbishops, Olba, has decided to side with him as well.
Lucifer has also discovered the key to magical power in this realm. Humans don't worship the gods in the same way that they do in Ente Isla, but feelings of despair are still a very powerful source of magic for the demonic types. That explains all the little crises that have been going on recently; Lucifer has been powering up on the humans' fears of death. And Olba has been helping him all the way.
So with betrayals of both Maou and Emi at the same time, perhaps the only way to defeat them is to team up.
As the story progresses, we start to see more than just the 'I'm Evil' side of Maou. Underneath all the bluster and claims of world domination is a quite honorable, hard-working person. All the traits that made him an excellent leader of demons also make him a great MgRonalds employee and friend to Chiho-chan. In fact, the same sorts of problems that we all go through, being broke and working terrible jobs, have pretty much the same solutions whether you're a human or a deposed Devil King.
Highs: Even as we get more of Maou's backstory, it's also nice to see Emi's friends and allies.
Lows: The manga follows the anime quite closely, and while it's a fun read, it doesn't give as much extra material as it could.
Verdict: The Devil is a Part-Timer Volume 2 is still a fun book, although the story might be better told in either the Light Novel or the anime.
Further Reading: The Devil is a Part Timer (Light Novel), Moribito, Rin-ne