Frieren. Beyond Journey's End. Volume 2: Kanehito Yamada

The adventure is over but life goes on for an elf mage just beginning to learn what living is all about.
Elf mage Frieren and her courageous fellow adventurers have defeated the Demon King and brought peace to the land. But Frieren will long outlive the rest of her former party. How will she come to understand what life means to the people around her?
At Eisen's urging, Frieren and her apprentice Fern head north seeking the land where heroes' souls are said to rest, which also happens to be the location of the Demon King's castle. Along the way, they meet Eisen's apprentice, whose fighting skills may come in handy-though the Demon King is long gone, his surviving minions have unfinished business with Frieren!