The Seven Mysteries Investigative Team Forms!

Synopsis
Sōsha talks about an urban legend about the Academy. Ehō gets scared while other students are interested. Himawari suggests investigating the places involved with the Academy's Seven Mysteries at night. Kae joins the group, so Kawaki complains about having to tag along. Himawari prepares the route to investigate all the mysteries. Ran and Suzu try to one up each other. Kura produces several trinkets while looking for ink for Yuina's pen. Shino arrives and tells them that while they can stay after hours, they have to clean the Academy as part of their training. The students leave, misremembering Shino's name. Kawaki offers to clean up, and Shino regrets not having much interaction with students lately. At night, they enter the Academy. Kae splits from the main group, and explains to Kawaki there's no way the Seven Mysteries are real, so to preserve everyone else's dreams, she had Batora fake them. Kae convinces Kawaki to help them. The rest of the group notices their absence. Kura wonders if one of the mysteries got to them, and the twins try to assure one another it's ok for them to leave. Batora and Kawaki scare the group as moving anatomical models. Sōsha flees in fear. In the training area, kunai barely miss them, but when Himawari turns the lights on, no one else is there. In a bathroom, Batora uses Water Release to scare them with red paint. Ran and Suzu flee. In the courtyard, Kawaki and Batora carry a statue of the Third Hokage, making it appear to move on its own. Himawari chases after it, and activating her Byakugan, sees it's Kawaki and Batora carrying it. She lets them go, pretending to the others she couldn't catch up. Kae returns to the main group, and Kawaki wonders why she's so committed to this. Batora explains that as heir, she was never able to act as a child, or play with friends and even her younger brother. He believes Kae is taking the opportunity to reclaim these experiences. Kawaki sympathises with the situation. When Kae returns, she notices his enthusiasm for continuing to scare the students. In the director's office, Iruka's portrait takes on a monstrous appearance, and a long tongue comes out of the frame. Everyone is scared, and Kura flees. Kae explains to Kawaki that while they're called Seven Mysteries, there are only six known mysteries, the nature of the seventh one also a mystery. Only Himawari, Ehō, and Yuina remain to check on the next mystery, a mirror that drags those reflected on it to another world. A shrouded figures appears above them, but it's not Batora, who arrived late over organising the supply room. Ehō and Yuina faint, and Kawaki attacks the figure, who dodges him and flees. Kae wants to uncover the figure's identity, and goes after it. Kawaki tells Himawari to take care of her friends, so he and Batora go after Kae. The mysteries they faked before all manifest for Kae, Kawaki, and Batora through the Academy. Kae thinks the mysteries are angry with them over being faked. They decide to check the faculty room, since none of the mysteries are associated with it. There, they find Shino, who gets covered in glowing pain, and explains that he was cleaning the faculty room. He doesn't know anything about mysteries, but determines that his insects were responsible, since Shino uses them to clean more effectively. The remaining students arrive, Yuina and Ehō fleeing over thinking the glowing Shino is a ghost. Leaving the building, Sōsha wants to write about it in the school paper. The twins continue to tease each other. Kae asks Kawaki not to reveal what they did to Himawari. The next day, the group tells the other students about their experiences, and the glowing ghost of the faculty room becomes the seventh mystery. Shino is pleased the students are talking about him in a way. Kawaki deduces Himawari discovered everything with her Byakugan, but she confesses she thought it was all real at first, and is glad Kae had so much fun. Kawaki thanks her.