The Telepathy Club is told that they are going to be shut down by the student council due to lack of members. It was then that one of the members, Inukawa, thought of possibly getting Mob to join. However, Mob gets a call from Reigen about taking care of an incident at Highso Girls' Academy...

It's great that Mob joined the Body Improvement Club, but he suddenly faints as he's running along the riverside. His wish is to get stronger and to be able to get closer to his beloved Tsubomi-chan. One day, as Mob is feeling troubled, a woman with a strange mask approaches him... Progress toward Mob's explosion: 20%.

Mob is finally pushed to his limit when he has to face Sakurai, Muraki, Matsuo and Ishiguro of the upper echelon. But then, he comes to a rather surprising decision...

Reigen received a phone call at his office, the Spirits and Such Consultation Office. The client asked him to find out what the black shadow that kept destroying his fields actually was. Meanwhile, back at Salt Middle School, Kamuro announces that he's going to resign from the position of student council president. Elections to decide a new student council president are going to be held and Mezato convinces Mob to run as a candidate, but...

After hanging out with the Body Improvement Club and Telepathy Club more, Mob starts to feel joy like he'd never felt before. One day while he's having fun with them, he gets a call from Reigen, spoiling his fun. Mob asks Reigen to stop summoning him so suddenly, and Reigen just handles the situation in his usual overbearing manner. And because of something very minor, a gap forms between them. Reigen is forced to go on jobs without Mob, forcing him to reexamine himself.

The day for the annual marathon and Salt Middle School was drawing nearer. Mob proclaims that if he places in the top 10 he'll tell Tsubomi how he feels about her. Everyone around him cheers Mob on and he starts training hard every day until the day of the event. Meanwhile, Tsubomi and her friend Miki go to Reigen's Spirits and Such Consultation Office with a request. Ritsu happened to be at the office, helping out in Mob's absence, but he hears Tsubomi say something rather surprising.

The Cultural Tower floats above Seasoning City. The final battle between Mob and Suzuki was about to begin. Mob is almost overwhelmed by the fact that he's able to completely release his powers, but then, he sees his younger brother, Ritsu. Mob regains his composure and he faces off with Suzuki, but Suzuki's power is too great. Mob finally gives up on trying to talk things out and puts everything he has into this battle. Who will be the victor?