Tanaka-san is a legendary hotel man (concierge), and after his death, he became a legend in the underworld. In the underworld, Mei works at the dilapidated Hotel Helheim. It was once a glorious hotel, and one where Mei has many fond memories. One day, Tanaka-san appears, ready to restore the Hotel Helheim to its former success. Mei will become the famous Tanaka-san's assistant, as he works to make Hotel Helheim a top-class underworld hotel!

Originally published in Jump Square as a 3-volume series from November 2014 to September 2015, the series was later republished under the Shonen Champion Comics label from December 2019 to January 2020. The volume count reflects the republished version, as it is the only one currently available.