Tonari no Jiisan

Yuki, a girl living in a rural town, studies art with a goal of becoming a painter in the big city. One day, her older sister decides to leave town to fulfill her dream. Yuki rides the train with her to see her off, but on the way there, Yuki is assailed by a strange phenomenon!? Reality or an illusion... a chilling horror!

(Source: Shounen Gahousha, translated)