Death came on swift wings. A soul, blessed by a goddess, falls to the land and enters his new life. He clings to a single memory, the defining moment of his previous life. Now he learns how to succeed in his new life as a new dungeon heart. To become the best dungeon he can be, he partners with the one existence all dungeons need: his bonded dungeon pixie.

In the aftermath of the demonic invasion, everyone is left to recover. Claire is worried about Doc's unending sleep. Fiora and her adventurers have split up, and the royal family mourns the loss of the prince and princess. Meanwhile, people are baying for blood as news spreads, and the church comes in to eliminate any demonic forces remaining. Tensions rise as the clergy begins its own agenda with the dungeon. Through it all, a town comes together with a unique bond to Doc.

The dungeon adventures continue with Doc, Claire, and company. With the win over the Tomb of the Forgotten King, they are as strong and curious as ever. While the town recovers from the attack, Doc settles in with his new powers and improves his dungeon to new levels. New slime evolutions, traps, and floors incoming! Meanwhile, something is rising in the dark in Duren. To counter this, Prince James takes the center stage and decides to have his coronation ceremony in the dungeon town.

The Empire's plans have come to fruition. Duran has fallen, and with it the other city-states of Nehatra. Only the dungeon town remains safe, but for how long? While the leadership struggle to deal with the crisis, the dungeon dwellers watch on. As Doc continues to unlock new slime evolutions, Rowen deepens his bond with Milly, and the two experience much together. When the final attack begins, will Rowen and Doc stand with the townspeople? Why has Doc been framed for murder? Who is the traitor lurking in the shadows?