Haruki is a high school freshman who swims competitively as part of the school's swimming club. He's best known for his childhood connection to the Mashiki twins—specifically, a chance encounter in kindergarten when a girl read him a fairy tale and gave him the book. Years later, he'd learn that girl was Mashiki Misao, the twin sister. Despite that early connection to Misao, Haruki ended up falling for her sister, Mashiki Miharu instead. The two reunited by coincidence at a convenience store near their high school, reigniting whatever spark had drawn him to her in the first place.
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