The Fairy's Secret Tea Party

The Fairy's Secret Tea Party is the final storyline of Humanity Has Declined and also the earliest point in its timeline. It consists of episodes 11 and 12 of the anime.

Summary
The story features a much younger Mediator as she starts attending school. She soon decides that she wants to get it over with as fast as possible and focus on getting good grades, which will allow her to skip grades. While she tries to remain inconspicuous, she is soon targetted by bullies, including Silver who locks her out of her dormitory one day and demands she solves riddles. After solving the first, The Mediator enlists the help of Ryobo230r, a robot caretaker, to break the lock. The next day Silver expresses disappointment in her. As The Mediator attempts to ignore her classmates and fast-track through her education, she starts to believe that Curly, a girl who attempts to befriend her, is the mastermind behind the bullies. One day she ends up saving a fairy from some of the boys and befriends it. When this fairy overhears her admit that she is lonely and desperate to make friends, it vanishes from the story after agreeing to grant her wish. Soon after, Curly starts skipping grades as well and is targetted by bullies too. When The Mediator helps her out, the two finally become friends. Curly then introduces The Mediator to The Wildrose Society, where she makes even more friends.

When The Mediator moves up another year, she becomes Silver's classmate and learns that she too was a member of The Wildrose Society. The Mediator investigates further and learns that Silver has been stealing books from the library and deduces that the reason Ryobo230r keeps running into walls is that the school used to have a different layout. Using this information she discovers Silver's secret yaoi stash and confronts her. In return for not revealing the information, Silver takes the protagonist on a tour through the school's secret hallways and, in the process, reveals all the scary secrets of the members of The Wildrose Society. This leads to The Mediator and Silver becoming friends and beginning to investigate the Fairy's Secret Tea Party, eventually causing them to befriend the members of The Wildrose Society again to help with the search. Years pass and the older members of the society graduate from school. In their final year, Silver, Curly and The Mediator are the only members left and discover a room full of Ryobo models. This causes The Mediator to panic as she begins to remember the fairy she met years before. Eventually, the three all graduate and a small, bittersweet ceremony is held, as the school has been torn down now that it is no longer needed. Sometime later, Silver visits the village and delivers a broken Ryobo230r, asking The Mediator if she can maybe fix it up. When she brings it inside, the fairy who heard her wish for friendship pops out and The Mediator bursts into tears. That night, The Mediator and the fairy have a tea party together, where The Mediator confirms that she is no longer lonely.

Trivia

 * A recurring bully throughout the story arc is first seen tormenting animals and wanting to hurt the fairy, but in the end he adopts a dog and become much friendlier.