Mob Psycho 100: Daiikkai Rei toka Soudansho Ian Ryokou - Kokoro Mitasu Iyashi no Tabi | Episode 1
Mob, Reigen, Dimple, and Serizawa, the newest member of the Spirits and Such Consultation Office staff, take a trip up to a secluded hot spring in Zebra Prefecture. Reigen received a request to discover the truth behind strange rumors about the inn.
(Source: Funimation)
Note: The OVA was screened at an anime event that took place at Kasukabe Citizens Cultural Center in Saitama Prefecture on July 7th, 2019.