Attack on School Castes

Attack on School Castes (進撃のスクールカースト) is a series of fake previews for the Attack on Titan manga, written and illustrated by Hajime Isayama. The series was published in each of the main manga's volumes from volume 21 to volume 34.

Overview
The story follows the misadventures of Eren Yeager and his friends as normal high school students.

A Few Words... Can Change Everything.
At school, Eren comes across Jean Kirstein bullying Armin Arlert. Eren fights off Jean, winning him Armin and Mikasa Ackerman's admiration.

Not Even Once.
Eren grows annoyed by his new friends' constant badgering to hang out with them and tries to ditch them in an alleyway. In the alley, he stumbles upon his school's janitor Levi buying a product from shady characters. The sellers claim that they are only giving him cleaning products but Eren flees in terror.

Candid Camera
Eren, Armin, and Mikasa approach Mr. Smith and Dr. Zoë to ask them about Levi but turn away in fear after noticing Levi's cleaning products with them. Later Eren is accosted by Levi and forced to help the janitor clean.

The Princess of the Better-Than-Yous
As the Do-Gooder Club holds a meeting, Historia Reiss silently resents the clique of friends she has for being shallow and boring. She sees Eren pass by and takes solace knowing that Eren, as a fellow loner, must understand how she feels. However, she is bewildered to learn that Eren has made friends with the school's nerds and Levi. Resenting Eren for his newfound friends Historia tells her clique that he did something awful to her.

Bullying Isn't Cool.
Eren is continuously bullied by the students at school, unaware of what is going on until Armin reveals that rumors have spread that he did something to Historia. Historia is mortified by what her clique has done to Eren but is unwilling to admit that she made up the rumor, so when he comes to confront her she attacks him herself.

Don't Believe Armin's Twisted Words!
Video of Historia and her friends beating up Eren spread throughout the school, resulting in them being ostracized. On Armin's suggestion, Eren approaches Historia in front of the whole school and apologizes to her for starting their confrontation, saving her from ridicule. As he leaves, Armin begins planning ways to blackmail her for the favor she now owes Eren.

A Little Something Called a Ouija Board!
Mikasa and Armin convince Eren to use an Ouija board with them. To everyone's shock, the board begins moving and Marco admits that he was the culprit. As the board moves a second time Eren suggests that Marco was the one moving it again and Armin and Mikasa are annoyed that he would make such a tasteless joke about a dead student.

I Do Feel Ashamed About the Reveal Being a Dream.
While sitting in class Eren grows bored and begins lamenting how uneventful his life is. A scream comes from the hallway and Eren emerges to find zombies attacking the school. Ecstatic that his boring life has been interrupted, Eren begins fighting off the zombies and demands the students follow him to safety.

Eren awakes from his dream and begins crying.

No, Eren! Don't Do It!
Eren laments that his life feels even more boring after the dream he had about a zombie apocalypse. He considers trying to do something to endanger humanity himself if a cataclysmic event is not going to happen, but his thoughts are interrupted by two children. The children try to talk to him about their religion but Eren brushes them off, scolding them for making their friend walk around in rags carrying a huge bucket. As he walks off he is grabbed by strangers in a white van. He wakes up to find himself tied up in the middle of a cult meeting.

Believers Will be Saved
The cultists try to get Eren to reveal what their god Ymir told him. Eren insists he does not know what they are talking about, but his words only convince the cultists all the more that he has seen her. As the cultists rejoice, Eren notices government members among them and is horrified to realize that he will not be able to rely on the authorities to rescue him. As Eren is lamenting his sorry situation, his classmates break into the building and rescue him, ferrying him away by car. However, the cultists are not willing to give him up easily.