When Kenji Tomosaka moved to a new coastal town, many years ago, he met a girl on the beach who is playing with some hermit crabs. She runs away crying after Kenji puts a crab on her head. When he gets back to his new home he finds out the girl is his next door neighbor and that his and her balcony are close enough he could jump from one to the other. In the present time Kenji wakes up after a strange dream then heads over to wake up Nanami Konoe. He finds her lying in the space between her bed and her wall and helps her out of it. Now begins the story of these two close childhood friends.