Haibane Renmei, Shoujo Shuumatsu Ryokou Recommendations
Both shows have a similar mood of comfort but also an unknown danger in the distance. They both have characters that don't fully understand their surroundings and gradually learn more as they spend time in the world. Haibane Renmai is much more a story of personal discovery, Shoujo Shuumatsu Ryokou is more about the world itself through the eyes of it's characters.
Both series potentially deal with the afterlife. Both series have a laid-back but melancholy feel to them and a slow, slice-of-life pacing. Both series are about calm, peaceful human interaction in an otherwise unsettling and ambiguous world.