Re:ZERO -Starting Life in Another World-, Chapter 3: Truth of Zero, Vol. 6 (manga) — Tappei Nagatsuki

Rem...stop making that face. Please. A smile suits you so much better.
Subaru returns to Crusch Karsten's door intent on avoiding the mistakes that led to his latest fatal encounter. He proposes an alliance between Emilia's and Crusch's camps...and to sweeten the deal, he'll offer intel vital to their mutual survival: the exact time and place the memory-destroying White Whale will appear! Among those listening in is a warrior whose hatred of the demon beast is a lifelong obsession...How will Crusch's servant-"The Sword Devil," Wilhelm-react to this opportunity for revenge?