Sometimes when you meet someone, you just know they're going to be interesting, but when 13-year-old Yasaka Hajime meets an older girl while staying at his grandfather's house for summer vacation, he has no idea how much she's about to change his life! To begin with, while Arashi may only look a few years older than Yasaka, she's actually closer in age to his granddad! How is that possible? It seems that Arashi's not exactly human anymore, and besides being a ghost from 1945, she has an important mission that revolves around her ability to travel in time! Since Arashi can only travel temporally if she's accompanied by a living being from her current present, guess who's about to become her partner in paradoxity? It's time for everything to go a little crazy in NATSU NO ARASHI!