Subaru Natsuki and Emilia receive an invitation from merchant Anastasia Hoshin to the city of Priestella, known for its canal-fed watergates, and set out to attend. This manga adapts the light novels' fifth arc, continuing the pair's journey through the world Subaru keeps looping back through via his death-and-return power. New faces and old allies converge on Priestella as the arc's central mystery starts to take shape.