Frieren: Remnants Of The Departed, Vol 3 (Manga)

The demon envoys’ true intention is exposed, and Fern finally concedes to accepting Frieren’s help to fight them off.

However, Frieren already has her hands full with an old enemy—a 500-year-old Prime Demon with an undying army at her command—and Fern and Stark must hold their own against an arrogant blood-wielding demon, as well as another who can copy her opponent’s every skill…