Eren hears about the Survey Club, a secret club that works to learn the titans' weaknesses, and instantly wants to join. However, since the Survey Club is supposed to be a secret, he still has to join an official club and ends up in the Wall Cleanup Club. On the plus side, at least the Wall Cleanup Club has cool vertical maneuvering gear.
Armin enters the picture when he's forced to attend school in order to give his class a chance of winning special ramen. Later, all the first years battle against the upperclassmen. The losers will be forced to go to the school's folk dance with the titans.
Most of my knowledge of Attack on Titan comes from the anime, since I'm still not very far into the manga. I knew enough to recognize most of the characters and notice the way Nakagawa had tweaked their defining characteristics for this skewed new world. Levi was still obsessed with cleaning (come to think of it, it's kind of odd that he wasn't in the Wall Cleanup Club), Eren was still obsessed with taking out the titans, Armin still preferred to stay out of the way, and Mikasa still propped Eren up with her skills and general scariness. I kind of wish that Nakagawa had either continued the “Eren's obsession with the titans is kind of racist” thread or not included it at all, because it was quickly dropped in favor of the titans legitimately being gross bullies (their favorite thing to do to students they disliked was pick them up and suck on them).
While I enjoyed seeing how Nakagawa had incorporated details from the original series into this parody series, most of the jokes didn't work for me. Eren's behavior towards the titans earned him a Hitler joke, Sasha went from being “Potato Girl” to “Foodstamp Girl,” the “titans suck people” thing was just gross, and Levi, arguably the best character from the original series, was barely in this volume.
I doubt I'll be continuing with this. Reading a parody series I already feel so-so about that's based on a manga series I'm having trouble working up the willpower to continue isn't really appealing. However, I did at least learn something new from this volume: I hadn't realized that Hange's gender was supposed to be a mystery. I don't think I've gotten that far into the manga, and I assumed Hange's gender based on the character's female voice actor in the anime. The translator's almost gleeful refusal to state Hange's gender or give Hange a gendered title or honorific is an ongoing joke in this parody.