Death March to the Parallel World Rhapsody, Vol. 6 (light novel) (Volume 6) (Death March to the Parallel World Rhapsody, 6);

After their journey down the river, Satou and crew finally arrive at the old capital just in time for the martial arts tournament, along with some fireworks, a ball at the castle, and sightseeing in the Ougoch Duchy. But the followers of the demon lord are plotting in the shadows...