In Search of a Scenery I've yet to See. 枯れ始めの山茶花

A girl who was cleaning her older brother’s room, who was her last family member, finds a diary.
Inside of it, the wishes of her brother -who was ill with a strange sickness- to journey outside were written.
After being left all alone, she decides to go on a journey in place of her brother, and make his wish come true.