While struggling to make friends after his parents’ divorce, Koyomi Takasaki meets Kazune Takigawa, but apparently, they already have. Kazune reveals that she’s from World Line 85, an alternate universe in which she and Koyomi are lovers. But in a reality where moving between dimensions is natural, could Koyomi be the one from another world?
maybe a series of splits toward 
the same direction occurred,
könnte doch eine sich immer
wieder in die gleiche Richtung spalten,
puede que uno fluya
hacia la misma dirección
puede que uno fluya
hacia la misma dirección
bifurquant à plusieurs reprises
dans la même direction,
si è creato un flusso che ripete le ramificazioni
 verso una stessa direzione,
какие-то стали развиваться похожим образом?