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?
But the way she carried herself 
only read as "Kazune" to me.
Nach ihrem Verhalten zu urteilen
sah sie für mich nur wie Kazune aus.
Su comportamiento
me parecía el de Kazune.
Su comportamiento
me parecía el de Kazune.
Pourtant, son apparence
était identique à celle de Kazune.
A vederla, mi sembrava Kazune.
Mas o jeito dela de agir só me
fez pensar que é a Kazune...
Но сколько бы ни вглядывался…
я видел в ней лишь Кадзунэ.