The deities of the Chutlhu mythos who live in ordinary high school student Yasaka Mahiro's home - Nyarko the Nyarlathotepian, Kuuko the Cthughan, and Hasuta the Hasturian - are enjoying the wonders of Earth entertainment yet again. They drag Mahiro along as they indulge in video games, shopping, cosplay, and more...

The Celaeno Library in the Pleiades star cluster is home to the largest book collection in the universe. It's said that even variants of Yiu-th only handed out at events can be found there. Mahiro is dragged along for some reason as Nyarko goes there to return a book. Hasuta, a former worker at the library, does his best to show Mahiro around, but they soon encounter two evil deities who have infiltrated the library...

The troubles from the library continue as the group travel to the ancient city of Alaozar. Before Nyarko can dispense justice the Great Old Ones pull an unexpected move.

Kurei Tamao is known as the "Walking Speaker." Not only is she the one to go to about gossip, but she's also famous for her advice on love. She's even had students from other schools ask her "What should I do about my cross-dressing childhood friend?" Knowing that, Nyarko decides to ask Tamao what she should do in order to get closer to Mahiro...

As usual, the Yasaka household living room is the gathering area for the deities and they're rowdy as ever. However after Mahiro's request that they make their own private living space, Nyarko, Kuuko, and Hasuta finally start building their rooms. A little worried, Mahiro decides to check on each of the rooms, and then they are suddenly visited by Kuuko's cousin, Kuune, who brings Kuuko news about a marriage appointment that's been set up for her...

To try to chase Kuune away, Mahiro and Kuuko keep acting like a couple, but Kuune still isn't convinced after seeing their awkward date, adding that she can't see the subtle lust for each other in each other's eyes. After having to see Mahiro and Kuuko act like their are engaged to each other, Nyarko finally...

Mahiro's mother, Yoriko, wins some tickets in a lottery for them to all go to the pool. Nyarko wears an amazing sexy and commando bathing suit to try to tempt Mahiro, as well as asking him to rub sun tan oil on her in an indoor pool. As Tamao works at the takoyaki stand that Luhi runs at the pool, she notices that Luhi seems to be troubled by something and tries to help her out...

Shanta-kun expresses that she'd like to be of some use to Mahiro who is always taking care of her and her master, so Kuuko gives her some red and blue candy. As soon as she ate it, she turned into a little girl! Shanta-kun tries really hard to be of some help to Mahiro, but Nyarko doesn't seem to like that. "There's no way that my pet is this little girl!" she said, as she chased them around...

"Yasaka Household, I have returned!" Kuuko's cousin, Kuune, seems rather mad that she had been left alone for so long. Once Mahiro and the others get to school, there is a strange aura surrounding it. Their classmates have fallen under a mass hypnosis and human-shaped flames attack the group. At this rate, the Earth is in danger! Is this the work of Kuune, or...

Nyarko is usually happy and hyper, but she's caught a cold and is stuck in bed. Nyarko is smitten by Mahiro, who's being a little nicer than usual. It's then that they get a report that an intruder has shown up at the North Pole. They leave Nyarko behind to recover and find that Mi-go was waiting for them...

The whole group goes camping on a day off. Nyarko grills some suspicious meat on the BBQ and Mahiro won't eat it. Nyarko's friend, Atko, had sent them some chocolates, but Mahiro won't eat that, either. As they wander the forest, they find an old mansion. They attempt to explore it, but a rather unexpected surprise awaited them...

The Banshin had been built in a day rather than 500 years, and Nyarko, Kuuko, and Hasuta are ordered to leave Earth as a result because they aren't needed anymore. The group goes to check to see what the Banshin actually is, as it determines if they really do have to leave or not. Will Mahiro have to say goodbye to Nyarko, Kuuko, and Hasuta?