Our Journey to the End of the Ceasing World by Yorozuya Tadahito

Translated from Japanese Completed Fantasy Adventure Post-apocalyptic
The story revolves around a boy and a girl who travel together through a world that is gradually nearing its end. A mysterious illness has emerged that erases the very existence of everyone who suffers from it. The story does, however, not focus on the tragic aspect of this fairly post-apocalyptic setting, but rather shows the people and events the two travelers come across during their journey.

Alternative names : Tabi ni Deyou, Horobiyuku Sekai no Hate Made

1: Tabi ni Deyou, Horobiyuku Sekai no Hate Made