The Devil Is a Part-Timer!, Vol. 24 (manga)

With all the pieces in place, Satan and his companions set off for the ancient devil overlord's stronghold-Satanas Arc! Back in present-day Sasazuka, Chiho resolves to tell Maou her true feelings once more. Meanwhile, Maou is shocked to find out what Emi has decided to do for her future. As the past comes to a close, so does the story of the demon king working as a part-timer!