Mob Psycho 100 Reigen -The Miraculous Unknown Psychic-

Mob Psycho 100 Reigen -The Miraculous Unknown Psychic- is a feature-length OVA produced by Studio BONES and released on March 18, 2018. It is a recap of the first season, spanning from the beginning of the series to the 7th Division Arc, but told mostly from the perspective of Reigen with his own insights and details added to the story. It also served as the announcement of Mob Psycho 100 II, the second season of the anime.

Prologue
The story opens with Reigen watching a TV program known as The Buzz List Principle in the Spirits and Such Consultation Office. On the program, a psychic known as Kirari Sophia advertises her recently-published book, which has already seen great commercial success. Inspired by the program, Reigen calls Mob into the office and tells him they are going to write and release a book detailing their recent experiences fighting against evil spirits and the 7th Division of Claw. When questioned about publishing costs, Reigen explains he'll start a crowdfunding campaign to cover it.

Chapter 1: As the Protector of Seasoning City
Reigen first tells the stories of how he easily defeated the Ceiling Crasher and the Boss with his salt-based special techniques, not even needing to call Mob in to help. He also details his encounters with the many citizens of Seasoning City who he managed to help with his other special techniques. This concludes chapter one. However, Mob is confused, remembering that he was the one who defeated the Ceiling Crasher. Reigen reassures him that he will have a place in the next chapter.

Chapter 2: As a Master Who Guides His Disciple
Reigen recaps the story of how Mob approached him and how he took him under his wing as a disciple. He details how Mob quickly came into his own as a psychic and defeated the giant spirit lurking in the Boss' tunnel, as well as the Scent-Ghoul at the girls' academy. He also tells the story of Mob's encouter with Dimple and the (LOL) Cult, and the destructive battle between Mob and Teruki Hanazawa at Black Vinegar High School.

It's revealed that Mob himself has been writing this chapter at home, as Reigen allowed him to write it out however he wanted to, being his part of the story after all. Ritsu notices how hard he's been working and tells him to not overwork himself, inspiring Mob to write about Ritsu next. He explains his relationship with his brother, including their difference in psychic powers. He tells the story of how Ritsu awakened his own powers and was subsequently kidnapped by the Claw esper Koyama.

Chapter 3: The One Who Fights Evil
Mob meets back up with Reigen to continue writing the next day. In the story, Reigen explains that he decided to go to save Ritsu, infiltrating the 7th Division hideout on his own. In a badly-edited sequence, Reigen's head pasted on Teruki's body battles against Terada in the woods outside the hideout and easily defeats him. He also takes credit for defeating Koyama, Matsuo, Miyagawa, and Takeuchi, though he graciously lets Mob keep the credit for beating Tsuchiya, Mukai, and Muto. Mob questions this choice, but Reigen assures him that all books dramatize their events to some extent.

Final Chapter: As a Member of the Masses
Back to the story, Mob is reunited with Ritsu and the team begins to head back out, though they are stopped by the remainder of the 7th Division Scars. The rest of the fight plays out about as it does in the anime, with Ritsu and Teruki fighting off the Scars while Reigen urges Mob not to fight. Reigen is struck from behind by Sakurai, though he survives the attempt and "unleashes his psychic powers" to beat the Scars into submission. However, when Ishiguro still persists, another sequence plays out where Reigen's head pasted on Sho's body defeats him. Reigen then summarizes that he had finally managed to save Mob's brother Ritsu from Claw and stop Claw's plans of world domination.

Epilogue
Mob, now in the Telepathy Club and Body Improvement Club's shared room, finally finishes writing the book and gains applause from his peers. Mezato tells him she knows a good place to print some copies, but before they can leave Teruki and Ritsu enter the room. Teruki says he heard about the book and decided that, since it's non-fiction, it should be fact-checked before it's released. Inspired, the Telepathy Club, Mezato, and Dimple all agree to help too. Upon reading, they are all horrified by the book's constant inaccuracies.

Back at Spirits and Such, Reigen has received the first copy of the printed book and begins to read it in front of Mob. However, he is greatly troubled when he discovers all of his embellishment is gone and that the book is now entirely non-fiction. He complains that he isn't even the main character of the book anymore, and that now he looks like a total con artist. Mob explains the intervention of his peers, and Reigen tells him they'll have to rewrite the whole thing again. However, when he checks the crowdfunding page, he finds that they didn't have enough money to get the book published anyways, reaching only 1% of their monetary goal. Disappointed, Reigen decides to take Mob out for ramen to end the night.

At the ramen shop, Reigen reveals that he was the only one who donated to the crowdfund, stating that 0% would look sketchy so he thought he'd start it off. Afterwards, Reigen heads to the Happy Trails bar and orders an extra sour drink. He wonders out loud when something good will happen; as if on cue, the TV next to the bar turns on with an important announcement - Mob Psycho 100 season two has been greenlit.