Demon King Daimao (2010)

S1E4 The Isolation Cell is Fun?

Thanks to Keena's intervention, Junko and Akuto patch things up. Yet during a mana control lesson, he accidentally knocks her out cold again. His teacher, Mitsuko, suggests he enter the Mental Self-Discipline Chamber. Inside the place where people are rumored to have died, Akuto sinks into despair. Korone and Keena inexplicably tag along, leaving him torn between them. Then they discover a strange map. Keena wonders if it leads to treasure. The next day, she copies it, and it spreads across the entire school, becoming the academy's hottest gossip. But Fujiko notices something familiar on the map.