A demon king has appeared in a neighboring kingdom and the king has to figure out how to deal with it. Meanwhile, Saitou makes a mistake which sets off a trap that sends him to one of the lower levels of the dungeon.

Adventurers from all over the kingdom flock to the new area that Saitou discovered. Saitou wants to go and investigate the curiosity that first lead to the discovery. Meanwhile, the king orders his allies to retrieve a hidden treasure from the new area.

There is a way to save the witch, Rahvella, from her curse, but will Kisurugi truly be willing to pay the price? And when the method of Saitou’s arrival in this world is discovered, will it change things between him and the others?

Saitou and the others have returned to their everyday lives. Then, one day, Lafanpan takes a bath in a mysteriously pattered cup and something completely unexpected happens.