Rooftop is the 57th chapter in the Gakkou Gurashi! manga.
Summary[]
The School Life Club is ready to leave Saint Isidore University. Before they leave, Yuki sees that Touko had wanted to say something and asks her about it. Touko says, "A lot has happened in your short time here but I would be happy if you think that good things happened too..."[1] Yuki and Kurumi reply that they will. Kurumi then pulls out her right hand for a handshake, but then realizes that it was the same hand that Aosoi had touched. Kurumi begins to pull her arm back but Touko grabs it and tells them, "We're all glad that you guys came!"[2] Both groups smile at each other. While Yuki and Touko were talking, Rii-san tells Sino that she is leaving. Sino tells Rii-san to be careful and that they will be waiting for their return. Rii-san agrees and Sino waves Guuma-chan the plushie's arm and says goodbye. Everyone says their goodbyes and the School Life Club gets inside the RV but Aosoi was seen already inside, as to Yuki and Kurumi's surprise. As Miki walks in, Hika sees an expression on Miki's face. Before they drive off, Yuki gives them one last wave goodbye. After they drive off, Aki spots that Hika was thinking of something and asks her about it. However, Hika reports that it was nothing.
Now with Rii-san driving and Kurumi sitting shotgun, Miki was staring outside the window. Suddenly, Yuki ends a discussion, looking at Miki, who was confused but agreed anyways. Yuki then points out that Miki wasn't even paying attention at all. Trying to catch up, Miki asks, "What were you talking about?"[3] Yuki replies that they were talking about the kinds of gifts that the Randall-san has to offer. Rii-san looks back to say that wasn't even close.
Back from the end of the previous chapter, Aosoi says that things have gotten interesting. She explains that even if the medicine/cure was imperfect, Kurumi had somehow endured it. Yuki was confused but Aosoi believes that Kurumi is the key to solving everything. This surprises everyone.
Miki begins to clarify to us mentally that the idea was to make a serum from Kurumi, but to do that, they must head to Randall Corporation because they may have better equipment. Before she could finish, Yuki pokes her and says that she could at least act like she is paying attention. Miki apologies but Yuki tells her it was okay. Rest assured, Yuki is almost sure of it that everyone will be okay.
Rii-san spots a coffee shop and parks the RV. Aosoi questioned if something went wrong but Rii-san wants to take a break. Yuki agrees. Miki walks up to the front of the RV and sees that Kurumi was asleep. She takes mental notes that Kurumi has been sleep more often, but wasn't sure if it was a good or bad thing. Miki turns around to exit, while Aosoi was questioning why they had to leave the RV. Miki explains that the RV doesn't provide enough space to do anything, because of this, they take breaks to stretch. Aosoi understands and stays behind. Yuki, Rii-san, and Miki (who is carrying a bat) begun to go out for a walk.
It all makes sense now!
Before Miki could go, Aosoi began to say that the RV was such a wonderful vehicle, but had questioned as to where they had gotten it from. Miki then says that it was from a shelter which could have been similar to the university's. Aosoi was confused about the "shelter" Miki was speaking of. Reflecting back from chapter 32, Miki describes to Aosoi about the shelter they had gone to. She explains that because the entryway was sealed shut, they had to enter through the rooftop. Remarkably, Miki points out that the rooftop was covered with dust. Miki begins to think for a moment, while Aosoi had wanted to hear it all. Thinking back at it again, Miki concludes that the Aerial Infection had really happened as she had thought.