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.

Mob, Reigen, Dimple, Serizawa, take a trip up to a secluded hot spring called Ibogami Hot Springs in Zebra Prefecture. Reigen happened to get a request from the matron there to discover the truth behind the strange rumors going around there and save the inn. Ritsu and Teru also join in on this trip but on their way there, Reigen and Serizawa start nodding off on the train and somehow get sucked into an eerie parallel world...