Koyomi Araragi, a third-year high school student, wakes up in a weird, empty emptiness after an encounter with oddity expert Izuko Gaen, only to be met by a happily familiar face in an ominously alien setting. Araragi navigates the webs of his history and the perplexities of the present with the support of his lover Hitagi Senjougahara in pursuit of answers. However, fate sends him back to the eccentric transfer student Ougi Oshino, who makes an unexpected proposal that threatens to unravel the very foundation on which he is based. Araragi learns a reality not meant to be shared as he peels back the layers of mystery surrounding an apparition.