Humanity Has Declined

妖精さんの、ひみつのこうじょう

After speaking with the Fairies about problems the humans have been having, mysterious things start to show up around the village.

妖精さんの、ひみつのこうじょう

The group continues to be pulled apart by a mysterious forces. The UN Mediator is the only one to make it to the conference room where the truth is...

妖精さんたちの、さぶかる

Y was assigned to work on the Human Monument project, but instead kicks off the BL Manga revolution.

妖精さんたちの、さぶかる

Y, Mediator, and the Assistant must find a way to escape or risk losing their sanity.

妖精さんたちの、おさとがえり

As the village prepares an electric-powered festival for the Human Monument Project, the heroine hears from the fairies that they are leaving to avoid the electromagnetic waves from the festival that are deadly to them. They leave behind a good luck charm and a curious manual explaining the dangers that come if no fairies are met during the day. During the festival, the heroine meets a curious girl named Pion, who is searching for her companion. The next day, the heroine and her assistant are sent to explore an underground structure, where they get trapped. As they search for the exit, the charm the heroine received turns into a fairy who tries to lead them towards water but instead comes across a group of acidic slimes. As they face more dangers upon reaching a computer room, they are rescued by Pion.

妖精さんたちの、おさとがえり

As Pion, revealed to be a robot who the heroine now calls P-ko, joins the party, they encounter her companion Oyage, a similar robot who calls himself O-taro, who wants to abandon his mission and live in the strange city. As he sends a killer digger truck after them, they all fall down a hole, winding up at an underground castle. The heroine and assistant are confronted by O-taro, who combines with the slimes to become a 'Killer Death Cat', though the fairies step in to help them. With help from the fairies, P-ko manages to defeat O-taro using a super powered microwave, which in turn restores their memories. After the gang manage to escape the city, it is revealed P-ko and O-taro, whose real names are Pioneer and Voyager, were deep space probes that gained humanoid form. O-taro makes P-ko realise that deep inside, like himself, she doesn't want to leave the warmth of the solar system. Hearing these thoughts, the heroine sabotages the electric generator, stopping P-ko and O-taro from being able to leave before reworking them to become wind-up powered.

妖精さんたちの、じかんかつようじゅつ

As the heroine is sent by her grandfather to look for his assistant, she encounters someone who looks exactly like her. Things only get stranger as she starts to encounter a lot of deja vu and encounters more versions of herself, with no clear memory over what is happening. She soon learns it to be the work of the fairies, who are manipulating time in order to get several copies of the heroine to make sweets for them. After several loops resulting in hundreds of clones making sweets, the heroine soon encounters a village full of dogs where the assistant lies.

妖精さんたちの、じかんかつようじゅつ

As the heroine reflects on her multiple timeloops, she focuses on the details about the assistant given to her by her grandfather and the doctor looking after him. During a certain timeloop between the fourth and fifth times, the heroine finally encounters the assistant, finding him to be an exciteable and lecherous young boy calling himself the Ringo Kid. After hearing more about him from her doubles during the fifth time, the heroine meets the assistant again on the sixth, this time finding him to have a gentler and more plain personality, believing he had finally found his own personality, using the doubles to get opinions from others about how he should be.

妖精さんの、ひょうりゅうせいかつ

After an increase in fairy population leads to bullying, the heroine is sent to accompany asylum seeking fairies to find a new home for them. Through various circumstances, the heroine ends up stranded on an island in the middle of the ocean, along with a group of pessimistic fairies who declare her the queen of their new nation. The fairies' motivation to work on building their new nation soon increases their population. The nation soon evolves into a bustling civilization dedicated to serving its queen, who begins living in luxury. Upon cultivating a plant that can produce candy, the fairies' research and development soon turn the nation into a literal candy island. However, after a lapse in judgment causes everyone to build monuments everywhere, the island is soon ruined and devoid of food and water, sending it into poverty. The heroine feels they should leave the island, but remains trapped by a rainstorm caused by the collective depression of the fairies. After the island ends up collapsing on itself, the heroine returns to dry land and her daily life.

妖精さんの、ちきゅう

The heroine begins her job as a mediator and finds it not to be what she expected. Whilst observing an abandoned site, she has her first encounter with a group of fairies and brings some of them home with her. After getting over the initial worries, the heroine finds the fairies to be quite talkative and curious and gives them some names, only to be tasked with naming all the other fairies as well. Finding the abandoned site she found them at turned into a metropolis overnight, she gives the fairy population a naming dictionary so they can decide on their own names. The next day, the heroine finds herself hailed as a god and ends up causing chaos when she tries to pass the responsibility onto someone else, leading the city to be destroyed.

妖精さんの、ひみつのおちゃかい

The heroine thinks back to when she was ten and began attending school, having to start at the lowest grade. As she decides to remain inconspicuous and focus on skipping through the grades, she finds herself the target of bullying from some of the other students, including a young Y, leading her to alienate a girl referred to as 'Curly' who tries to become her friend, believing her to be the mastermind. One day, the heroine rescues a fairy from a group of bullies and has it tag along with her. As the stress of her school life leads the heroine to admit to herself that she feels lonely, the fairy does something before disappearing. The heroine finds Curly has joined her in skipping grades, also facing some bullying from jealous peers. As the heroine decides to repay some of her kindness, she finds Curly to be disturbingly affectionate with her. Curly then moves into the heroine's dorm and invites her to join a secret tea party.

妖精さんの、ひみつのおちゃかい

Whilst spending time having tea parties with the Wildrose Society, the heroine learns that Y was once part of the society. A year later, the heroine moves up to year 4 and becomes Y's classmate. She soon learns Y had been stealing books to build her own yaoi library. In exchange for her not revealing her secret, Y sneaks the heroine into the rooms of the other Wildrose members, revealing their hidden agendas, including how mentally unstable Curly is. After learning all of this, the heroine joins Y in searching for a ture fairy tea party, and over the years they rekindle with the Wildrose Society. As the heroine, Y and Curly discover a room full of robots, the heroine remembers about the fairy she met years ago. After everyone graduates and the school is torn down, the heroine is visited by Y, who brings her the robot from the school dorms, which is soon revealed to contain the fairy she had met at school.