Re:ZERO -Starting Life in Another World-, Vol. 21 (light novel) — Tappei Nagatsuki

The Witch Cult has finally been driven from the Water Gate City, but the turbulent events have left deep scars on Pristella. Far too many people have even been robbed of their names and memories. In order to save them, Subaru and his friends set off on a dangerous journey to the Pleiades Watchtower. To get there, they will need to cross the Auguria Dunes, home to vicious demon beasts of every stripe and so treacherous a place that even Reinhard was forced to turn back. The only way they have any chance of making it across is to trust the guidance of a spirit bearing the name of a certain witch and a demon beast tamer who once tried to kill everyone in Roswaal Manor. With such unsettling traveling companions and a still-sleeping Rem along for the ride, Subaru will need to stay on his toes to make sure everyone reaches their destination in one piece...