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?
If we just let them live 
their respective lives,
Wenn sie ihre beiden
Leben so weiterführen,
Si viven sus vidas con normalidad,
Si viven sus vidas con normalidad,
En continuant leurs vies ainsi,
Se la vita di ognuno andrà come deve andare,
Se continuarem a viverem suas vidas de forma
separadas, eles jamais irão se encontrar.
А там, если оба пойдут
своим жизненным путём,