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?
And thus my very first 
confession of feelings...
Damit ist das erste
Liebesgeständnis meines Lebens …
Y así, la primera confesión de mi vida…
Y así, la primera confesión de mi vida…
Ma première tentative
d’avouer mes sentiments…
Ed è così
E assim, minha primeira
declaração de amor na vida...
Вот так вот
первое в моей жизни признание в любви…